F(x) = -3(x + 2)(x - 5)^3 > 0
(x + 2)(x - 5) > 0
x + 2 > 0 or x - 5 < 0
x > -2 or x < 5
-2 < x < 5
Therefore, the stated interval is false.
Answer:
11.1 years
Step-by-step explanation:
The formula for interest compounding continuously is:

Where A(t) is the amount after the compounding, P is the initial deposit, r is the interest rate in decimal form, and t is the time in years. Filling in what we have looks like this:

We will simplify this first a bit by dividing 2000 by 1150 to get

To get that t out the exponential position it is currently in we have to take the natural log of both sides. Since a natural log has a base of e, taking the natual log of e cancels both of them out. They "undo" each other, for lack of a better way to explain it. That leaves us with
ln(1.739130435)=.05t
Taking the natural log of that decimal on our calculator gives us
.5533852383=.05t
Now divide both sides by .05 to get t = 11.06770477 which rounds to 11.1 years.
Step-by-step explanation:

10 times a number y
3 subtracted by A number x
12 times a number n
The concept useful in finding the answer to this item is ratio and proportion, the ratio of the height of your friend with the shadow casted should be proportional to the height of the rock with the length of the shadow it cast. That is,
5.5 ft / 18 ft = x ft/ 209.5 ft
The value of x from the equation above is 64 ft.