Who tryna help me with this math

Find (f • g) when f(x) = x^2 + 5x + 6 and g(x) = 1/x+3

Nikitich [7]

Answer:

option D

Step-by-step explanation:

$f(x) = x^2 + 5x + 6$

$g(x)= \frac{1}{x+3}$

(fog)(x) = f(g(x))

Plug in g(x) in f(x)

We plug in 1/x+3 in the place of x in f(x)

$f(g(x))= f(\frac{1}{x+3})= (\frac{1}{x+3})^2 + 5(\frac{1}{x+3}) + 6$

To simplify it we take LCD

LCD is (x+3)(x+3)

$\frac{1}{(x+3)(x+3)}+5\frac{1*(x+3)}{(x+3)(x+3)}+\frac{6(x+3)(x+3)}{(x+3)(x+3)}$

$\frac{1}{x^2+6x+9}+\frac{(5x+15)}{x^2+6x+9}+\frac{6x^2+36x+54}{x^2+6x+9}$

All the denominators are same so we combine the numerators

$\frac{1+5x+15+6x^2+36x+54}{x^2+6x+9}$

$\frac{6x^2+41x+70}{x^2+6x+9}$

Option D is correct

8 0

3 years ago

Read 2 more answers

Cindy took her five grandchildren to the movies, where she offered to buy all of them popcorn and candy. A popcorn bag costs $4.

Svetradugi [14.3K]

Answer:

She buys 5 boxes of popcorn and 6 boxes of candy

Step-by-step explanation:

this is because 5 times 4.00 is 20$ and 2.50 times 6 is 15$

15 + 20 is 35

so your answer is 5 boxes of popcorn and 6 boxes of candy

hope this helped :D

6 0

3 years ago

Two sides of a triangle measure 10 centimeters and 15 centimeters what is the measure of the third side

Lady_Fox [76]

Between Greater Than 5 And less than 25

Rule says the sum of two sides must be greater than the third
You get e extremes by subtracting the numbers and the other by adding them

8 0

3 years ago

Help me please,Thanks

Naily [24]

0.5, you would divide 0.375 to cancel out the height and then divide 0.75 (the new volume after you divided 0.375 by the height) by 1.5 to cancel out the x

7 0

3 years ago

You have measured the systolic blood pressure of a random sample of 25 employees of a company located near you. A 95% confidence

Alla [95]

Answer:

$122 \leq \mu \leq 138$

The 95% confidence interval would be given by (122;138)

And the correct interpretation for this case is:

c. If the procedure were repeated many times, 95% of the resulting confidence intervals would contain the population mean systolic blood pressure.

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % where by a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=25-1=24$

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,24)".And we see that $t_{\alpha/2}=2.06$

Now we have everything in order to replace into formula (1), for this case we got:

$122 \leq \mu \leq 138$

The 95% confidence interval would be given by (122;138)

And the correct interpretation for this case is:

c. If the procedure were repeated many times, 95% of the resulting confidence intervals would contain the population mean systolic blood pressure.

6 0

3 years ago