Using tan(x) = sin(x)/cos(x) provided that cos(x) is not equal 0

How do I use tan(x) = \frac{sin(x)}{cos(x)} ?

In this post we use tan(x) = \frac{sin(x)}{cos(x)} provided that cos(x) \neq 0 , as a part of the Prelim Maths Advanced course under the topic Trigonometric Functions and sub-part Trigonometric Functions.

This video covers the trigonometric identity of tan(x) = \frac{sin(x)}{cos(x)} and how it is used in questions.