Question

Form correct pairs from the given options:

• A. cosec ${26}^{\circ }$
• B. cos $2^{\circ }$
• C. cot ${18}^{\circ }$
• D. sin ${58}^{\circ }$

Answer 1

We know that,

1) sin (${90}^{\circ }$- $\theta$) = cos $\theta$
$\therefore$ sin ${88}^{\circ }$ = sin (${90}^{\circ }$- $2^{\circ }$)
= cos $2^{\circ }$

2) sec(${90}^{\circ }$- $\theta$) = cosec$\theta$
$\therefore$ sec${64}^{\circ }$ = sec(${90}^{\circ }$- ${26}^{\circ }$)
= cosec ${26}^{\circ }$

3) tan (${90}^{\circ }$- $\theta$) = cot $\theta$
$\therefore$ tan ${72}^{\circ }$ = tan (${90}^{\circ }$ - ${18}^{\circ }$)
= cot ${18}^{\circ }$

4) cos (${90}^{\circ }$- $\theta$) = sin $\theta$
$\therefore$ cos ${32}^{\circ }$ = cos (${90}^{\circ }$- ${58}^{\circ }$)
= sin ${58}^{\circ }$