Find the rate at which the function f(x) = x4 – 2x3 + 3x2 + x + 5 changes with respect to x.
Given,
y = x4 – 2x3 + 3x2 + x + 5
We need to rate of change of f(x) w.r.t x.
Rate of change of a function w.r.t a given variable is obtained by differentiating the function w.r.t that variable only.
So in this case we will be finding dy/dx
As, y = x4 – 2x3 + 3x2 + x + 5
Now, differentiating both sides w.r.t x –
∴ )
Using algebra of derivatives –
⇒
Use:
∴
⇒
∴ Rate of change of y w.r.t x is given by –