Question

1. Instantaneous rate of change of distance gives
speed of te moving object. The distance varying
with time as S=2.5t^2 +13t - 6 Calculate.
the speed of object at t = 1second.
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Answer 1

We need to differentiate it to get an expression that gives velocity.

$\frac{d}{dx} 2.5 {t}^{2} + 13t - 6$

is equal to 5t + 13

Hence the speed at t = 1 sec is 5(1) + 13 = 18 m/s.