Use Quotient Rule to Find Derivative of y=tanx

In this first of two videos, we find the derivative of the tangent function using the Quotient Rule and the derivatives of the Sine and Cosine functions. It is a good idea to memorize the fact that the derivative of the tangent function is the secant function squared, BUT if you forget, you can always reconstruct it! You will need to know your Pythagorean Identities which are also shown in the video.