Question

Let f be the function defined by f(x) = 2{x^3} - 4x + 1. Which of the following is an equation of the line tangent to the graph of f at the point x = - 1?

Answer 1

I don't see any choices.

y = 2x^3 - 4x + 1
dy/dx = 6x^2 - 4
at x = -1, dy/dx = 6-4 = 2
y = -2 + 4+1 = 3

so we have slope = 2, point is (-1,3)

equation of tangent:
y - 3 = 2(x + 1)

dress it up to whatever form you need.