What is the basic trigonometric identity you would use to verify that secx sinx = tanx

The answer is for the problem shown above is:

 secx=1/cosx

 The explanation is shown below:

 1. To solve this problem you must apply the following proccedure:

 2. You have  to verify if secx sinx=tanx, so, you have:

 3. You know that secx=1/cosx, and tanx=sinx/cosx, therefore:

 (secx)(sinx)
 (1/cosx)(sinx)
 sinx/cosx
 tanx