If `cottheta-t a ntheta=s e ctheta` , then `theta` is equal to `2npi+(3pi)/2, n Z` b. `npi+(-1)^npi/6,\ n Z` c. `npi+pi/2, n Z` d. none of these

Explanation

To solve the equation \( \cot \theta - \tan \theta = \sec \theta \), we will follow these steps:

### Step 1: Rewrite the trigonometric functions
We know that:
- \( \cot \theta = \frac{\cos \theta}{\sin \theta} \)
- \( \tan \theta = \frac{\sin \theta}{\cos \theta} \)
- \( \sec \theta = \frac{1}{\cos \theta} \)

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