If S = (4t + 3)(t - 2), find ds/dt when t = 5 secs.

If S = (4t + 3)(t - 2), find ds/dt when t = 5 secs.

Answer Details

$s=(4t+3)(t-2)$
$\frac{ds}{dt}=(4t+3)\left(1\right)+(t-2)\left(4\right)$
= $4t+3+4t-8$
= 8t - 5
$\frac{ds}{dt}(t=5secs)=8\left(5\right)-5$
= 40 - 5 
= 35 units per sec