The height of the diver is given by h= -4.9t^2 + 8.8t + 3 where h is the meters the height above water at time t seconds. What is the maximum height of the diver and how long did it take to reach maximum height?

Question

anonymous · Answer

Hiii there... differentiate the expression w.r.t 't' and solve for derivative =0 for maxima or minima...

phi · Answer

if you do not know calculus, you could do this.
the equation is a parabola,  of the form
$$ h = a t^2 + b t +c $$
the t value where this parabola "peaks"  is at
$$ t= \frac{-b}{2a} $$
in this case, b= +8.8,  and a = -4.9

replace a and b in the above formula with those numbers to find the t value where the parabola peaks.

once you find the t value, use that number in the equation for h to find the maximum height.

anonymous · Answer

Or in simpler terms ,
 as I think is the way to prove @phi 's fact.... complete the squares of the expression and you would easily get to find what value of ''t'' corresponds to max height...