posted by Hanna on .
Find an equation of the line that is tangent to the graph of f and parallel to the given line
Function: f(x) = x^3
Line 3x-y+1 = 0
._.; I know the derivative of the function is 3x^2 and I do have the answer in the back of my book just need the way to get it..
Sorry in advance-- I don't know how to find the answer, but I'm willing to help all I can.
First, rearrange the equation of the line to make it y=-3x-1. Since we need to find a line parallel to this one, we know it needs a slope of -3.
What is the answer the back of the book gives? Sometimes it's possible to work backwards from the answer.
Sorry that's as far as I could go.
I'll try to help you out all I can--I'm trying to work it out right now.
:3 yep I got there too.
It was y=3x+2 I think.
It doesn't matter though XD I'll just ask my teacher when I get there