How do you find the equation of the line tangent to f(x) = 6x^2 - 1 at x = 3?

1 Answer
May 28, 2018

y=36x-55

Explanation:

f(x)=6x^2-1 , color(white)(aa) xinRR

f'(x)=12x

f(3)=53

f'(3)=36

The equation of the tangent line at A(3,f(3)) will be

y-f(3)=f'(3)(x-3) <=>

y-53=36(x-3) <=>

y=36x-55

graph{(y-6x^2+1)(y-36x+55)=0 [-41.1, 41.1, -20.55, 20.55]}