Answer:
The interval of increase of g(x) is
.
Step-by-step explanation:
The interval of increase occurs when first derivative of given function brings positive values. Let be
, the first derivative of the function is:


The following condition must be met to define the interval of increase:

The first term is always position due to the quadratic form, the second one is a first order polynomial and it is known that positive value is a product of two positive or negative values. Then, the second form must satisfy this:

The solution to this inequation is:

Now, the solution to this expression in interval notation is: 
Answer:
a. the investment earns 4%
b. yes
Step-by-step explanation:
The "rule of 72" says that an investment earning compound interest at x% will double in value after 72/x years. That is, ...
f(x) = 72/x
__
<h3>a.</h3>
We interpret f(4) to mean Becky's friend is interested in the doubling time for an investment that earns 4% interest.
__
<h3>b.</h3>
Using the above formula, ...
f(4) = 72/4 = 18
The friend's math is correct.
The height is the measurement from the base to the top straight up.
The Slanted height is the height from base to top on one face of the pyramid.
Format: y = mx + b
m = slope, b = y intercept
Solution: slope: -2, y intercept: 0