Prove the following identites.
 
\(\frac{1 - cot^2 \ C}{tan^2 \ C - 1} = cot^2 \ C\)
 
Proof:
Answer variants:
\(\frac{cos^2 \ C}{sin^2 \ C}\)
\(cot^2 \ C\)
\(\frac{sin^2 \ C}{cos^2 \ C}\)
\(tan^2 \ C\)
LHS= 1cot2Ctan2C1= 1ii1=sin2Ccos2Csin2Csin2Ccos2Ccos2C=cos2Csin2C= i