Answer:
It is increasing in the interval (-∞, 3/2).
Step-by-step explanation:
y = -x^2 + 3x + 8
The derivative is:
dy/dx = -2x + 3
This is the slope of tangent to the curve so when f(x) is increasing
-2x + 3 > 0
-2x > - 3
x < 3/2
So it is increasing in the interval (-∞, 3/2)
