Question

`(\text{i})\text{ }\frac{\cot 54^\text{o}}{\tan36^\text{o}}+\frac{\tan 20^\text{o}}{\cot 70^\text{o}}-2`

Answer 1

We have,

`\frac{\cot 54^\text{o}}{\tan 36^\text{o}}+\frac{\tan20^\text{o}}{\cot70^\text{o}}-2`

`=\frac{\cot (90^\text{o}-36^\text{o})}{\tan36^\text{o}}+\frac{\tan 20^\text{o}}{\cot(90^\text{o}-20^\text{o})}-2`

`=\frac{\tan 36^\text{o}}{\tan36^\text{o}}+\frac{\tan 20^\text{o}}{\tan20^\text{o}}-2`

= 1 + 1 – 2 = 0