Find the equation of the line that is:
Tangent to the function
Write the equation of the tangent line in point-slope form.
We know that the point of tangency happens at
. Evaluate the function, , to find the point.
Evaluate the derivative,
, to find the slope.
Normal to the tangent line at
Definition: A 'normal line' is perpendicular to a tangent line at the point of tangency.