If \(\frac{cos^2 \ \theta}{sin \ \theta} = p\) and \(\frac{sin^2 \ \theta}{cos \ \theta} = q\), then prove that \(p^2 q^2 (p^2 + q^2 + 3) = 1\).
 
Proof:
 
\(\frac{cos^2 \ \theta}{sin \ \theta} = p\) and \(\frac{sin^2 \ \theta}{cos \ \theta} = q\)
 
\(p^2=\)
 
\(q^2=\)
 
\(p^2 q^2=\)
 
\(p^2 q^2 (p^2 + q^2 + 3) =\)
 
By simplyfing this then applying the formula
then we get the result.
Answer variants:
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