A ball is thrown straight up The distance s of the ball from

A ball is thrown straight up. The distance s of the ball from the ground is given by the function s(t)=240+3t-4t^2

Find the maximum height attained by the ball. (Enter only the number without the unit).

Solution

s(t)=240+3t-4t^2

s\'(t)=0+3*1-4*2t

s\'(t)=3-8t

for maximum height s\'(t)=0

3-8t=0

t=3/8

maximum height =s(3/8)=240+3*(3/8)-4*(3/8)^2

maximum heigh=240+(9/8)-(9/16)

maximum height =s(3/8)=240.5625

maximum height =241