What is the period of the sinusoidal function

Here is the problem.....√(15x + 10) = 2x+3

to remove the square root, we do the opposite which is to square everything.

(√(15x + 10))² = (2x + 3)² (the square negates the square root)
15x + 10 = (2x +3)(2x + 3) (use the distributive property to continue)
15x + 10 = 4x² + 6x + 6x + 9 (combine like terms)
15x + 10 = 4x² + 12x + 9 (subtract 15x and 10 from each side)
-15x - 10 -15x - 10
0 = 4x² - 3x - 1 (factor completely)
(x - 1) (4x + 1) (set each to equal 0)

x - 1 = 0 4x + 1 = 0
x = 1 4x = -1
x = -1/4

place both into the equation to check for reasonableness...we see the negative number is not reasonable, but the x value of 1 is a solution.

answer is 1

4 0

3 years ago

What are two equivalent forms for the polynomial 3x - 2x -2x? How do you get them?

Lynna [10]

Simplify 3x -2x -2x = 3x + -2x + -2x
Combine like terms: 3x + -2x + -2x = (3x + -2x +-2x) = -x
answer is: -x

5 0

3 years ago

A researcher working in a Human Resources department was interested in gender and sales figures so he conducted a t-test. The me

irina1246 [14]

Answer:

$d = \frac{78.24 -66.25}{\sqrt{\frac{7^2 +7^2}{2}}}= 1.713$

For the interpretation we consider a value for d small is is between 0-0.2, medium if is between 0.2-0.8 and large if is higher than 0.8.

And on this case 1.713>0.8 so we have a large effect size

This value of d=1.713 are telling to us that the two groups differ by 1.713 standard deviation and we will have a significant difference between the two means.

Step-by-step explanation:

Previous concepts

The Effect size is a "quantitative measure of the magnitude of the experimenter effect. "

The Cohen's d effect size is given by the following formula:

$d = \frac{\bar X_1 -\bar X_2}{\sqrt{\frac{s^2_1 +s^2_2}{2}}}$

Solution to the problem

And for this case we can assume:

$\bar X_1 =78.24$ the mean for females

$\bar X_2 =66.25$ the mean for males

$s_1 = s_2= 7$ represent the deviations for both groups

And if we replace we got:

$d = \frac{78.24 -66.25}{\sqrt{\frac{7^2 +7^2}{2}}}= 1.713$

For the interpretation we consider a value for d small is is between 0-0.2, medium if is between 0.2-0.8 and large if is higher than 0.8.

And on this case 1.713>0.8 so we have a large effect size

This value of d=1.713 are telling to us that the two groups differ by 1.713 standard deviation and we will have a significant difference between the two means.

4 0

3 years ago