Given 3a/(a+1)^2
To make the denominator a cube, you would have to multiply by 1 or (a+1)/(a+1)
yielding 3a(a+1)/(a+1)^3
(3a^2 + 3a) is the equivalent numerator
The girls are closer. Her feet are 1/2 the distance away from the surface pool, the boys are 3/4 away.
F(x) = 2x + 1 when x <= -5
Now -10 is less than -5 so we plug x = -10 into 2x +1:-
f(-10) = 2(-10) + 1 = -19 answer
Now f(x) = x^2 when -5< x < 5
x =2 is within this range so f(2) = 2^2 = 4 answer
You can calculate the other 3 values by a similar method