Answer:
-15
Step-by-step explanation:
The solution of expression for x = - 4 is,
⇒ - 15
We have to given that,
An expression is,
⇒ 2x - 7
Now, We can simplify the expression for x = - 4 as,
An expression is,
⇒ 2x - 7
Plug x = - 4;
⇒ 2 × - 4 - 7
⇒ - 8 - 7
⇒ - 15
Thus, The solution of expression for x = - 4 is,
⇒ - 15
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HELP
Which of the following equations represents a line that passes through the points (-5,4) and (10,14)
|. y = 6/5x -2
||. 6x+5y=-10
I'll give you brain crown thingy if you get it right
The linear equation that passes through the two given points is
3y - 2x = 22
Which of the equations represents the line?Remember that a linear equation that passes through the points (x₁, y₁) and (x₂, y₂) has a slope:
a = (y₂ - y₁)/(x₂ - x₁)
In this case the points are (-5,4) and (10,14), then the slope is:
a = (14 - 4)/(10 + 5) = 10/15 = 2/3
Then the line is something like:
y = (2/3)*x + b
To find the value of b, you can replace the values of one of the points there.
14 = (2/3)*10 + b
14 - 20/3 = b
22/3 = b
Then the line is:
y = (2/3)*x + 22/3
3y = 2x + 22
3y - 2x = 22
That is the line that passes through the two points.
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Who is smart enough to know this answer ?
find the surface area of the prism
Answer: 132 cm cubed
Step-by-step explanation:
0.5*3*4*2=12
10*5=50
4*10=40
3*10=30
30+40+50+12=132 cm cubed
The Ozzie Chocolate Company is preparing to offer a new product in its candy offerings, the Minty Dark Chocolate Bite bar. Material costs per new candy bar are
$0.25 for chocolate, $0.02 for sugar, and $0.03 for mint flavoring. Labor costs of the new product are approximately $0.15 per bar. Adding a production line devoted to the new candy will cost $250,000 per year.
(a) If the sales price is $1.40 per candy bar, how many must the company make per year in order to break even? Assume that each bar made is sold at full price.
(b) What is the company's profit or loss if they make and sell 270,000 candy bars at the $1.40 price in the first year?
(c) About 20% of the food consumed in the U.S. is imported. Production in many industries has been offshored. What ethical issues do companies face when presented with the decision to move operations?
Answer:
a) 263,158
b) $164,500
c) Ethical issues companies face when deciding to move operations: job loss for employees, poor working conditions and exploitation of workers, negative environmental impact,...
Step-by-step explanation:
a)
Total cost = (0.25 + 0.02 + 0.03 + 0.15) x + 250,000
Total revenue = 1.40x
Setting the two equations equal to each other and solving for x, we get:
(0.45)x + 250,000 = 1.40x
0.95x = 250,000
x ≈ 263,158
b)
If the company sells 270,000 candy bars at $1.40 each, the total revenue generated is:
270,000 * $1.40 = $378,000
The total cost of producing 270,000 candy bars is:
(0.25 + 0.02 + 0.03 + 0.15) * 270,000 + $250,000 = $213,500
Therefore, the company's profit is:
$378,000 - $213,500 = $164,500
c)
Ethical issues companies face when presented with the decision to move operations: job loss for employees, poor working conditions and exploitation of workers, negative environmental impact,...
Both numbers have three significant figures. How many significant figures should be recorded for the answer to the division problem below?
\(43.6 \div 21.2\)
= [?] significant figures
Answer:
8 significant figures should be provided.
Step-by-step explanation:
I believe I am correct, but check your answer anyways.
HI PLEASE HELP ON QUESTION ASAP USING AVERAGE (MEAN) TO ANSWER QUESTION! IF UR ANSWER AND EXPLAINATION IS CORRECT ILL RATE YOU FIVE STARS, A THANKS AND MAYBE EVEN BRAINLIEST. PLEASE MAKE SURE YOU ANSWER MY QUESTION USING AVERAGES.
1) a meal for 6 cost £12 per person. as it is one of the diners birthday , the other 5 decided to pay for his meal. how much do each of the five friends need to pay?
Each of the five friends needs to pay £14.40 to cover the cost of the birthday person's meal.
To calculate how much each of the five friends needs to pay, we can use the concept of averages or mean.
The total cost of the meal for 6 people is £12 per person. This means that the total cost of the meal is 6 * £12 = £72.
Since the other five friends have decided to pay for the birthday person's meal, they will evenly divide the total cost of £72 among themselves.
To find the average amount each friend needs to pay, we divide the total cost by the number of friends paying, which is 5:
£72 / 5 = £14.40
Using the concept of averaging or finding the mean allows us to distribute the cost equally among the friends, ensuring fairness in sharing the expenses.
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PLEASE HELP
Which of the following inequalities is true according to the number line?
Answer:
A ≥ D
Step-by-step explanation:
find the approximate area of the sector
blank cm2
Answer:
If Im NOT MISTAKEN its 7.41
Step-by-step explanation:
What is 31+4 × [11-(1+3)] =
Answer:
59
Step-by-step explanation:
31+4 × [11-(1+3)]
31+4*[11-4]
31+4*(7)
31+28
59
The easy Answer is 59. When doing these types of questions remember:
Parentheses
Exponents
Multiplication
Divionsion
Add
Subtract
It took Todd 11 hours to travel over pack ice from one town in the Arctic to another town 330 miles away. During the return journey, it took him 15 hours.
Assume the pack ice was drifting at a constant rate, and that Todd’s snowmobile was traveling at a constant speed relative to the pack ice.
What was the speed of Todd's snowmobile?
Answer:
The speed of Todd's snowmobile was 22 miles an hour
Step-by-step explanation:
:))
The speed of Todd's automobile is 31 miles per hour.
What is speed?Speed is defined as the ratio of the time distance travelled by the body to the time taken by the body to cover the distance. Speed is the ratio of the distance travelled by time. The unit of speed in miles per hour.
Given that It took Todd 11 hours to travel over pack ice from one town in the Arctic to another town 330 miles away. During the return journey, it took him 15 hours.
For the first journey,
v₁ + v₂ = 330 / 11 ......................( 1 )
For the return journey,
v₂ - v₁ = 330 / 15 .........................( 2 )
From equation ( 1 ) and equation ( 2 ),
2v₂ = ( 330 / 11 ) + ( 330 / 15 )
2v₂ = ( 330 ) ( 31 / 165 )
v₂ = 165 ( 31 / 165 )
v₂ = 31 miles per hour
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Ben is a cyclist. On average he cycles 500 m in one minute 1.5.1 1.5.2 Determine the formula for calculating distance covered 1- Use the Table I below to determine the values of ABC and Ding formula from 15.1 Table 1: Distance Vs Time Distance (metres) 1 2 1100 TOTAL ACTIVITY 1:
The formula for calculating distance that Ben covered will be \(500 m/minute * Time.\)
What is the formula for calculating the distance?The distance between 2 points in physical space is the length of a straight line between them.
In physics and math, to calculate the distance covered by Ben while cycling, we can use the formula for distance which is: Distance = Speed × Time.
Given:
Ben cycles at average speed of 500 m/minute.
We will substitute the values into the formula which is:
Distance = 500 m/minute × Time.
Therefore, the formula for calculating distance that Ben covered will be \(500 m/minute * Time.\)
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What are the solutions of 3(x - 4)(2x - 3) = 0? Check all that apply.
-4
-3
- 를
c
3
4
Answer:
4 and 3/2
Step-by-step explanation:
\(x = 4 \)
\(2x = 3 \\ x = \frac{3}{2} \)
Pls help me
Here is triangle ABC:
No links pls
Answer:
\(Given: AC=1\)
∠A=0
\(Cos0=\frac{B}{H} =\frac{AB}{AC}\)
\(Cos0=\frac{AB}{1}\)
\(AB=Cos0\)
-------------------------
hope it helps...
have a great day!!
Answer:
AB = AC×cos theta= cos theta
Use the Venn diagram to determine the roster form of set (A-C)'
Using the Venn diagram to determine the roster form of set (A-C)' = { 1, 2, 5, 6, 7, 9, 10, 11, 12, 13, 14 }.
What are the elements for (A - C )?The difference of the sets A and C in this order is the set of elements which belong to A but not to C.
A - C = elements in set A but not in set C
A - C = { 3, 4 , 8 }
The A minus C complements include the following;
(A - C)' = { 1, 2, 5, 6, 7, 9, 10, 11, 12, 13, 14 }
Thus, using the Venn diagram to determine the roster form of set (A-C)' depends on the number of elements in the universal set.
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If 8 minus some number divided by 3 = 6 what is the number?
Answer:
n = 6
Step-by-step explanation:
Represent the unknown number by n. Then 8 - n/3 = 6.
Consolidate the constants on the left side: 2 - n/3 = 0, or n/3 = 2.
Multiplying both sides by 3 results in: n = 6
NO LINKS!!
45. Express 3log₅x + log₅y - 2log₅w as a single logarithm
46. Find the missing value: log21 -2log7 + log28 = log__
47. Expand ln[(x - 4)(2x+5)²]
Answer:
\(\textsf{45.} \quad \log_5\left(\dfrac{x^3y}{w^2}\right)\)
\(\textsf{46.} \quad \log 12\)
\(\textsf{47.} \quad \ln(x-4)+2\ln(2x+5)\)
Step-by-step explanation:
\(\boxed{\begin{minipage}{8cm}\underline{Log laws}\\\\Product law:\quad\:$\log_axy=\log_ax + \log_ay$\\\\Quotient law:\;\;\;$\log_a \left(\dfrac{x}{y}\right)=\log_ax - \log_ay$\\\\Power law:\quad\;\;\;\:$\log_ax^n=n\log_ax$\\\end{minipage}}\)
Question 45\(\begin{aligned}3\log_5x + \log_5y - 2\log_5w&=\log_5x^3 + \log_5y - \log_5w^2\\&=\log_5\left(x^3 \cdot y\right)- \log_5w^2\\&=\log_5\left(\dfrac{x^3y}{w^2}\right)\end{aligned}\)
Question 46\(\begin{aligned}\log21 - 2 \log7 + \log28 &=\log21 - \log7^2 + \log28\\&=\log21 - \log49 + \log28\\&=\log\left(\dfrac{21}{49}\right) + \log28\\&=\log\left(\dfrac{3}{7} \cdot 28\right)\\&=\log\left(\dfrac{84}{7}\right)\\&=\log12\end{aligned}\)
Question 47\(\begin{aligned}\ln \left[(x - 4)(2x+5)^2\right]&=\ln(x-4)+\ln(2x+5)^2\\&=\ln(x-4)+2\ln(2x+5)\\\end{aligned}\)
Rearrange the equation so u is the independent variable.
-12u + 13 = 8w - 3
w = __
Answer: w = -3u/2 + 2
Step-by-step explanation:
-12u + 13 = 8w - 3
-12u + 13 + 3 = 8w -3 + 3
-12u + 16 = 8w
w = -3u/2 + 2
PLEASE HURRY DUE TONIGHT
Mary is babysitting a 4-year-old. The little boy wants to play in the kiddie pool in the backyard. Mary knows that using the hose that is near the kiddie pool will take 30 minutes to fill up. The little boy has already asked 17 times if the pool is ready but she hasn't even turned on the water yet. Mary also knows that the hose from the front yard works faster and can fill the pool in 1/2 the time as the hose in the back yard. If she can use both hoses at the same time, how long will it take for the pool to fill up?
(PLEASE SHOW YOUR WORK)(I saw other people get 7.5 min and 75 min but those answers are incorrect.)
A. 5 minutes
B. 10 minutes
C. 22.5 minutes
Using both hoses will take 10 minutes to fill up the kiddie pool. Mary can fill up 1/3 of the pool using the front yard hose in 10 minutes and 1/6 of the pool using the backyard hose in 10 minutes.
To solve this problem, we need to use the concept of rates. Let's assume the rate of the hose in the backyard is x, so the rate of the hose in the front yard is 2x (because it is twice as fast as the other hose).
The combined rate of the two hoses is x + 2x = 3x, which means they can fill the pool in 30/3x = 10/x minutes.
We know that the area of the pool is 600 square feet and each small rock covers 20 square feet, so we need a total of 600/20 = 30 small rocks to cover the pool.
Since the mass of each rock is 20 grams, the total mass of all 30 rocks is 30 x 20 = 600 grams.
To find the density, we divide the total mass (600 grams) by the total volume of the rocks (30 x 20 cubic feet = 600 cubic feet)
Density = 600g / 600 cubic feet = 1g/cubic foot
Therefore, the answer is B. 10 minutes for the pool to fill up, and the density of the rocks is 1 gram per cubic foot.
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Determine which integers in the set S: {−2, −3, −4, −5} will make the inequality 4p − 7 ≥ 9p + 8 true.
PLS HELP ME
The integers in the set s: {-2,-3,-4,-5} will make the inequality 4p-7 \(\geq\) 9p+8 true are : -3, -4, -5
Let's solve the inequality first
4p -7 \(\geq\) 9p +8
Taking p's on the same side we will get :
-7 - 8 \(\geq\) 9p - 4p
-15 \(\geq\) 5p
Divide by 5 into both sides
-3 \(\geq\) p
i.e. p \(\leq\) -3
Therefore p must be less than or equal to -3
From the set, we have the numbers -3,-4,-5 which are less than or equal to -3
Hence the integers -3,-4,-5 will make the inequality 4p-7 \(\geq\) 9p+8 true
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How do you isolate the variable in an inequality?
For one to isolate the variable by using equation rules. Inverse inequality sign if multiplying/dividing by negative. Steps to isolate variable in inequality: Simplify, move constants with inverse operations. Divide coefficient to isolate variable. Reverse direction if using negative number.
What is the variable?Inequalities require you to apply the same principles as those used in equations when isolating a variable. For example, if there is an inequality 3x - 5 < 7. one can isolate the variable, by first:
Add 5 to both sides to be: 3x < 12.
Then divide both sides by 3: x < 4.
So, the variable x is one that is isolated, and the solution to the inequality is one where x < 4.
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15. The solutions to (x+4)2 - 2 = 7 are
1) -4+ 5
3) -1 and -7
2) 4+ 5
4) 1 and 7
I
Answer:
Step-by-step explanation:
(x + 4)^2 - 2 = 7 simplifies to
(x + 4)^2 = 5
We must isolate x. To do this, take the square root of both sides, obtaining:
x + 4 = ±√5
There are two roots/solutions. They are:
x = -4 + √5 and x = -4 - √5
You must include the square root operator (√). Use " ^ " to denote exponentiation.
The solutions to the given equation (x + 4)² - 2 = 7 when calculated are; 1 and 7
How to Solve Algebra Problems?We are given the equation as;
(x + 4)² - 2 = 7
Add 2 to both sides to get;
(x + 4)² = 9
Find the square root of both sides to get;
x + 4 = ±3
Thus;
x = 3 + 4 and x = -3 + 4
x = 1 and 7
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look at screenshot plz
related information for 30 employees at Gamma Technologies, Inc. These data include each selected employee’s gender (0 = male, 1 = female), age, number of years of relevant work experience prior to employment at Gamma, number of years of employment at Gamma, the number of years of post-secondary education, and annual salary. Create a scatter plot to show the relationship between prior experience and annual salary. What does the scatter plot reveal about the relationship?
Answer:
Kindly check attached picture
Step-by-step explanation:
Data:
Prior experience :
5
12
0
2
5
9
6
11
12
0
5
9
1
0
5
3
12
3
11
10
8
1
0
6
7
0
8
13
7
0
Annual salary:
37500
50912
29356
27750
97844
48442
40207
42331
87489
26118
40025
88763
35829
17784
54199
36932
93279
22100
49987
85471
52220
36109
23105
39455
49861
30327
31008
90874
57966
16500
Using the data above, the scatter plot obyaoon using statistical software is attached below, from the line of best fit, the regression equation which models the relationship between the two variables is ŷ = 4003.257X + 25172.868.
The trend of the best fit line shows a positive correlation between prior experience and annual salary. The correlation Coefficient value which shows the strength of the association gives a value of 0.7225 ; hence, depicting a strong positive correlation.
Rebecca is a real estate agent who would like to find evidence supporting the claim that the population mean market value of houses in the neighborhood where she works is greater than $250,000. To test the claim, she randomly selects 35 houses in the neighborhood and finds that the sample mean market value is $259,860 with a sample standard deviation of $24.922. The test statistic t for a hypothesis test of H0 : μ = 250.000 versus Ha : μ > 250.000 is t 2.34 , which has 34 degrees of freedom. If 0.01
A) Fail to reject the null hypothesis that the true population mean market value of houses in the neighborhood where Rebecca works is equal to $250,000.
B) Reject the null hypothesis that the true population mean market value of houses in the neighborhood where Rebecca works is equal to $250,000.
C) There is enough evidence at the α-: 0.05 level of significance to support the claim that the true population mean market value of houses in the neighborhood where Rebecca works is greater than $250,000.
D) There is not enough evidence at the α-_ 0.05 level of significance to suggest that the true population mean market value of houses in the neighborhood where Rebecca works is not equal to $250,000.
Answer:
There is enough evidence at the α-: 0.05 level of significance to support the claim that the true population mean market value of houses in the neighborhood where Rebecca works is greater than $250,000.
Step-by-step explanation:
We are given that Rebecca randomly selects 35 houses in the neighborhood and finds that the sample mean market value is $259,860 with a sample standard deviation of $24.922.
Let \(\mu\) = population mean market value of houses in the neighborhood.
So, Null Hypothesis, \(H_0\) : \(\mu\) = $250,000 {means that the population mean market value of houses in the neighborhood where she works is equal to $250,000}
Alternate Hypothesis, \(H_A\) : \(\mu\) > $250,000 {means that the population mean market value of houses in the neighborhood where she works is greater than $250,000}
The test statistics that would be used here One-sample t-test statistics because we don't know about population standard deviation;
T.S. = \(\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }\) ~ \(t_n_-_1\)
where, \(\bar X\) = sample mean market value = $259,860
s = sample standard deviation = $24,922
n = sample of houses = 35
So, the test statistics = \(\frac{259,860-250,000}{\frac{24,922}{\sqrt{35} } }\) ~ \(t_3_4\)
= 2.34
The value of t-test statistic is 2.34.
Also, P-value of the test statistics is given by;
P-value = P(\(t_3_4\) > 2.34) = 0.0137
Since our P-value is less than the level of significance as 0.0137 < 0.05, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.
Therefore, we conclude that the population mean market value of houses in the neighborhood where she works is greater than $250,000.
write a number to represent the situation: A withdrawal of $36
The number which represents the situation of a withdrawal of $36 is -$36.
In this question, we have to find out the number or integer which represents the situation of a withdrawal of $36. This question is from integers topic and for that we should have the definition of integers in our mind. So, an integer is defined as number which can be represented without the fractional form. It contains whole numbers and negative of natural numbers. The integers are generally denoted by the symbol 'Ζ'. And, the integers can be negative or positive.
In this question we have asked withdrawal of $36 from any source. So, withdrawal basically means money will decrease, so it will become negative.
To represent a withdrawal of $36, we will use the negative sign.
Hence, -$36 is the correct representation of the situation of a withdrawal of $36.
Therefore, -$36 is the required answer.
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Elise drew p pictures. Nora drew 70 fewer pictures than Elise. Write an expression that shows how many pictures Nora drew
Answer:
p - 70
Step-by-step explanation:
elsie drew = p70 less than p
nora drew = p - 70Answer:
p - 70
Step-by-step explanation:
We're looking for the number of drawings Nora made, which is 70 fewer than Elise's, p. In instances like this, always subtract the number of less drawn from the quantity drawn by the other person, which is 70 - p. However, this would almost certainly result in a negative response, which isn't feasible. If you flip them over, you'll get p - 70.
How do you find the volume of a pyramid height 10 length 8 width 6?
Answer:
just multiply everything together, to get volume.
Answer:
The general volume of a pyramid formula is given as: Volume of a pyramid = 1/3 x base area x height.
Step-by-step explanation:
A tank in the shape of a hemisphere has a diameter of 24 feet. If the liquid that fills the tank has a density of 92.5 pounds per cubic foot, what is the total weight of the liquid in the tank, to the nearest full pound?
The total weight of the liquid in the tank is approximately 12,628 pounds.
To calculate the weight of the liquid, we need to determine the volume of the hemisphere and then multiply it by the density of the liquid. The formula for the volume of a hemisphere is V = (2/3)πr³, where r is the radius of the hemisphere.
In this case, the diameter of the tank is given as 24 feet, so the radius is half of that, which is 12 feet. Plugging this value into the formula, we get V = (2/3)π(12)³ ≈ 904.78 cubic feet.
Finally, we multiply the volume by the density of the liquid: 904.78 cubic feet * 92.5 pounds per cubic foot ≈ 12,628 pounds. Therefore, the total weight of the liquid in the tank is approximately 12,628 pounds.
In summary, to calculate the weight of the liquid in the tank, we first determine the volume of the hemisphere using the formula V = (2/3)πr³. Then, we multiply the volume by the density of the liquid.
By substituting the given diameter of 24 feet and using the appropriate conversions, we find that the total weight of the liquid is approximately 12,628 pounds.
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Learning Task 4. Solve the problem. Estimate the total amount. Mr. Cruz's monthly
income is P75,000.00. He divide his income to the following expenses:
Food: P 22, 450.89
Recreation: P5, 676.63
Clothes: P 15,670.25
Transportation: P 10,067.15
Step-by-step explanation:
Answer: 21,135.08
Step-by-step explanation: because
22,450.89+5,676.63+15 ,670.25+10,067.15=53,864.92
so now 75,000 - 53,864.92 = 21,135.08 that's it
Heeeelp please, Can be zero or not?
with all steps and explanay.
The value of integral is 3.
Let's evaluate the integral over the positive half of the interval:
∫[0 to π] (cos(x) / √(4 + 3sin(x))) dx
Let u = 4 + 3sin(x), then du = 3cos(x) dx.
Substituting these expressions into the integral, we have:
∫[0 to π] (cos(x) / sqrt(4 + 3sin(x))) dx = ∫[0 to π] (1 / (3√u)) du
Using the power rule of integration, the integral becomes:
∫[0 to π] (1 / (3√u)) du = (2/3) . 2√u ∣[0 to π]
Evaluating the definite integral at the limits of integration:
(2/3)2√u ∣[0 to π] = (2/3) 2(√(4 + 3sin(π)) - √(4 + 3sin(0)))
(2/3) x 2(√(4) - √(4)) = (2/3) x 2(2 - 2) = (2/3) x 2(0) = 0
So, the value of integral is
= 3-0
= 3
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Answer:
\(3-\displaystyle \int^{\pi}_{-\pi} \dfrac{\cos x}{\sqrt{4+3 \sin x}}\; \text{d}x\approx 0.806\; \sf (3\;d.p.)\)
Step-by-step explanation:
First, compute the indefinite integral:
\(\displaystyle \int \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x\)
To evaluate the indefinite integral, use the method of substitution.
\(\textsf{Let} \;\;u = 4 + 3 \sin x\)
Find du/dx and rewrite it so that dx is on its own:
\(\dfrac{\text{d}u}{\text{d}x}=3 \cos x \implies \text{d}x=\dfrac{1}{3 \cos x}\; \text{d}u\)
Rewrite the original integral in terms of u and du, and evaluate:
\(\begin{aligned}\displaystyle \int \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x&=\int \dfrac{\cos x}{\sqrt{u}}\cdot \dfrac{1}{3 \cos x}\; \text{d}u\\\\&=\int \dfrac{1}{3\sqrt{u}}\; \text{d}u\\\\&=\int\dfrac{1}{3}u^{-\frac{1}{2}}\; \text{d}u\\\\&=\dfrac{1}{-\frac{1}{2}+1} \cdot \dfrac{1}{3}u^{-\frac{1}{2}+1}+C\\\\&=\dfrac{2}{3}\sqrt{u}+C\end{aligned}\)
Substitute back u = 4 + 3 sin x:
\(= \dfrac{2}{3}\sqrt{4+3\sin x}+C\)
Therefore:
\(\displaystyle \int \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x= \dfrac{2}{3}\sqrt{4+3\sin x}+C\)
To evaluate the definite integral, we must first determine any intervals within the given interval -π ≤ x ≤ π where the curve lies below the x-axis. This is because when we integrate a function that lies below the x-axis, it will give a negative area value.
Find the x-intercepts by setting the function to zero and solving for x in the given interval -π ≤ x ≤ π.
\(\begin{aligned}\dfrac{\cos x}{\sqrt{4+3\sin x}}&=0\\\\\cos x&=0\\\\x&=\arccos0\\\\\implies x&=-\dfrac{\pi }{2}, \dfrac{\pi }{2}\end{aligned}\)
Therefore, the curve of the function is:
Below the x-axis between -π and -π/2.Above the x-axis between -π/2 and π/2.Below the x-axis between π/2 and π.So to calculate the total area, we need to calculate the positive and negative areas separately and then add them together, remembering that if you integrate a function to find an area that lies below the x-axis, it will give a negative value.
Integrate the function between -π and -π/2.
As the area is below the x-axis, we need to negate the integral so that the resulting area is positive:
\(\begin{aligned}A_1=-\displaystyle \int^{-\frac{\pi}{2}}_{-\pi} \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x&=- \left[\dfrac{2}{3}\sqrt{4+3\sin x}\right]^{-\frac{\pi}{2}}_{-\pi}\\\\&=-\dfrac{2}{3}\sqrt{4+3 \sin \left(-\frac{\pi}{2}\right)}+\dfrac{2}{3}\sqrt{4+3 \sin \left(-\pi\right)}\\\\&=-\dfrac{2}{3}\sqrt{4+3 (-1)}+\dfrac{2}{3}\sqrt{4+3 (0)}\\\\&=-\dfrac{2}{3}+\dfrac{4}{3}\\\\&=\dfrac{2}{3}\end{aligned}\)
Integrate the function between -π/2 and π/2:
\(\begin{aligned}A_2=\displaystyle \int^{\frac{\pi}{2}}_{-\frac{\pi}{2}} \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x&= \left[\dfrac{2}{3}\sqrt{4+3\sin x}\right]^{\frac{\pi}{2}}_{-\frac{\pi}{2}}\\\\&=\dfrac{2}{3}\sqrt{4+3 \sin \left(\frac{\pi}{2}\right)}-\dfrac{2}{3}\sqrt{4+3 \sin \left(-\frac{\pi}{2}\right)}\\\\&=\dfrac{2}{3}\sqrt{4+3 (1)}-\dfrac{2}{3}\sqrt{4+3 (-1)}\\\\&=\dfrac{2\sqrt{7}}{3}-\dfrac{2}{3}\\\\&=\dfrac{2\sqrt{7}-2}{3}\end{aligned}\)
Integrate the function between π/2 and π.
As the area is below the x-axis, we need to negate the integral so that the resulting area is positive:
\(\begin{aligned}A_3=-\displaystyle \int^{\pi}_{\frac{\pi}{2}} \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x&= -\left[\dfrac{2}{3}\sqrt{4+3\sin x}\right]^{\pi}_{\frac{\pi}{2}}\\\\&=-\dfrac{2}{3}\sqrt{4+3 \sin \left(\pi\right)}+\dfrac{2}{3}\sqrt{4+3 \sin \left(\frac{\pi}{2}\right)}\\\\&=-\dfrac{2}{3}\sqrt{4+3 (0)}+\dfrac{2}{3}\sqrt{4+3 (1)}\\\\&=-\dfrac{4}{3}+\dfrac{2\sqrt{7}}{3}\\\\&=\dfrac{2\sqrt{7}-4}{3}\end{aligned}\)
To evaluate the definite integral, sum A₁, A₂ and A₃:
\(\begin{aligned}\displaystyle \int^{\pi}_{-\pi} \dfrac{\cos x}{\sqrt{4+3\sin x}}\; \text{d}x&=\dfrac{2}{3}+\dfrac{2\sqrt{7}-2}{3}+\dfrac{2\sqrt{7}-4}{3}\\\\&=\dfrac{2+2\sqrt{7}-2+2\sqrt{7}-4}{3}\\\\&=\dfrac{4\sqrt{7}-4}{3}\\\\ &\approx2.194\; \sf (3\;d.p.)\end{aligned}\)
Now we have evaluated the definite integral, we can subtract it from 3 to evaluate the given expression:
\(\begin{aligned}3-\displaystyle \int^{\pi}_{-\pi} \dfrac{\cos x}{\sqrt{4+3 \sin x}}\; \text{d}x&=3-\dfrac{4\sqrt{7}-4}{3}\\\\&=\dfrac{9}{3}-\dfrac{4\sqrt{7}-4}{3}\\\\&=\dfrac{9-(4\sqrt{7}-4)}{3}\\\\&=\dfrac{13-4\sqrt{7}}{3}\\\\&\approx 0.806\; \sf (3\;d.p.)\end{aligned}\)
Therefore, the given expression cannot be zero.