In Example 4, change the right side to tan x/sec x .

Data from Example 4

In proving the identity

we know that cot x = cos x/ sin x. Because sin x appears on the left, substituting for cot x on the right will eliminate cot x and introduce sin x. This should help us proceed in proving the identity. Thus, starting with the right-hand side, we have  

By showing that the right side may be changed exactly to sin x, the expression on the left side, we have proved the identity.

Transcribed Image Text:

sin.x COS X cotx