Question

Prove that cos35°co sec55° = 1​

Answer 1

LHS

$= > \frac{1}{sec35 ° } \times cosec55 ° \\ = > \frac{1}{sec(90° - 55 °)} \times cosec55 ° \\ = > \frac{1}{cosec55 °} \times cosec55 ° \\ = > 1$

LHS=RHS

Hence proved.

Remember:

sinA=1/cosecA => cosecA=1/sinA

cosA= 1/secA => secA=1/cosA

tanA=sinA/cosA=1/cotA

cotA=cosA/sinA=1/tanA

sin(90°-A)=cosA

cos(90°-A)=sinA

sec(90°-A)=cosecA

cosec(90°-A)=secA

tan(90°-A)=cotA

cot(90°-A)=tanA