Prove the following identities: `sec^4A-sec^2A=tan^4A+tan^2A`

Explanation

To prove the identity \( \sec^4 A - \sec^2 A = \tan^4 A + \tan^2 A \), we will start from the left-hand side and manipulate it to show that it equals the right-hand side.

### Step-by-step Solution:

1. **Start with the Left-Hand Side:**
\[ \sec^4 A - \sec^2 A \]
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