Derivatives of exponential functions

banfill_89 · Apr 17, 2008

Homework Statement

find the equation of the tangent to the curve defined by y=e^x that is perpendicular to the line defined by 3x+y=1

m= 1/3 (negative reciprocal of y=-3x+1)
derivative of e^x=e^x

i keep getting stuck at 1/3=e^x ( i know there's a way to solve for x i just can't remember)

the answer is x-3y+(1+ln3)=0

steelphantom · Apr 17, 2008

ln(e^x) = x. You can take the natural log of both sides of an equation.