Let's prove the given trigonometric identity:
\[\frac{1}{1 + \cot^2 \alpha} + \cos^2 \alpha = 1\]
We know the trigonometric identity:
\[1 + \cot^2 \alpha = \csc^2 \alpha\]
So, we can rewrite the expression as:
\[\frac{1}{\csc^2 \alpha} + \cos^2 \alpha = 1\]
We also know that \(\csc \alpha = \frac{1}{\sin \alpha}\), therefore, \(\csc^2 \alpha = \frac{1}{\sin^2 \alpha}\). Thus, we can write:
\[\frac{1}{\frac{1}{\sin^2 \alpha}} + \cos^2 \alpha = 1\]
Which simplifies to:
\[\sin^2 \alpha + \cos^2 \alpha = 1\]
This is a fundamental trigonometric identity, which is true. Thus, the original identity is proven.
Therefore, the given trigonometric identity \(\frac{1}{1 + \cot^2 \alpha} + \cos^2 \alpha = 1\) is correct.
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