Show that none of the following is an identity:
` (i) cos^(2) theta + cos theta =1 " " (ii) sin^(2) theta + sin theta =2 " " (iii) tan^(2) theta + sin theta = cos^(2) theta `

Explanation

To show that none of the following equations are identities, we will evaluate each equation by substituting a specific value for \(\theta\) and checking if the left-hand side (LHS) equals the right-hand side (RHS).

### (i) \( \cos^2 \theta + \cos \theta = 1 \)

1. **Substituting a value for \(\theta\)**:
Let's take \(\theta = 30^\circ\).

2. **Calculating LHS**:
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