Question

How do you differentiate `f(x)=7x^3-x^2+x` using the sum rule?

Answer 1

`f'(x)=21x^2-2x+1`

Explanation:

`d/dx(7x^3-x^2+x)=d/dx7x^3-d/dxx^2+d/dxx`, we can break up a derivative across sums or differences.

Thus,

`f'(x)=(3)(7)x^2-2x+1`

`f'(x)=21x^2-2x+1`