Question

How do you find the derivative of the function `f(t)=5t-9t^2`?

Answer 1

`f'(t) = 5 - 18t`

Explanation:

You need to learn the power rule for differentiation;
`d/dxx^n = nx^(n-1)`

Hence,
`f'(t) = d/dt(5t-9t^2)`
`:. f'(t) = 5d/dt(t^1) - 9d/dt(t^2)`
`:. f'(t) = 5(1)t^0 - 9(2t^1)`
`:. f'(t) = 5 - 18t`