Verify that \(\frac{\sin \ A}{\sec \ A + \tan \ A - 1} + \frac{\cos \ A}{\text{cosec}\: A + \cot \ A - 1} = 1\)
 
Proof:
 
LHS \(= \frac{\sin \ A}{\sec \ A + \tan \ A - 1} + \frac{\cos \ A}{\text{cosec}\: A + \cot \ A - 1}\)
 
\(= \)
 
\(=\)
 
\(=\)
 
\(=\)
 
\(=\)
 
\(=\)
 
\(= \)
 
\(=\)
 
\(= \)
 
\(= \)
 
\(= \frac{2 \sin \ A \cos \ A}{2 \sin \ A \cos \ A}\) 
 
\(= 1 = \) RHS
 
Hence, we proved.
Answer variants:
2sinAcosA1+2sinAcosAsin2A+cos2A
sinAcosecA+sinAcotAsinA+cosAsecA+cosAtanAcosA(secA+tanA1)(cosecA+cotA1)
1+cosAsinA+1+sinAcosA(secA+tanA1)(cosecA+cotA1)
2sinAcosA1+sinAcosA1+cosAsinA
21+sinAcosAcosA1+cosAsinAsinA
sinA×1sinA+sinA×cosAsinAsinA+cosA×1cosA+cosA×sinAcosAcosA(secA+tanA1)(cosecA+cotA1)
1+cosAsinA+1+sinAcosA1cosA+sinAcosA11sinA+cosAsinA1
2sinAcosA1+cosAsinA+sinA+sinAcosAsin2AcosAcos2A+sinAcosA
2sinAcosA1+2sinAcosA1
sinA(cosecA+cotA1)+cosA(secA+tanA1)(secA+tanA1)(cosecA+cotA1)