Question

How do you find the instantaneous rate of change of the function `y= x^2-4x` when x=1?

Answer 1

When `x=1`, `dy/dx = -2`

Explanation:

The 'instantaneous rate of change' is the same as the slope or gradient of the function and is found by calculating `dy/dx`.

`y=x^2-4x`

`dy/dx = 2x-4`

When `x=1`, `dy/dx = -2`