What is the equation of the line normal to #f(x)=(3x-1)(x+4)# at #x=-3#?
1 Answer
Jan 14, 2016
Explanation:
Take the derivative of the equation to find the slope of the tangent, and then the slope of the normal is the negative inverse.
First expand the equation to simplify getting the derivative:
At the point
The slope is
The equation of the normal is therefore
At the point
Plugging this back into the normal gives
The normal equation is therefore