prove that `1/(secA-tanA)-1/(cosA)=1/(cosA)-1/(secA+tanA)`

Explanation

To prove the equation

\[ \frac{1}{\sec A - \tan A} - \frac{1}{\cos A} = \frac{1}{\cos A} - \frac{1}{\sec A + \tan A} \]

we will solve both sides separately and show that they are equal.

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