Question

Sin18°/cos72°+tan26°/cot64°=

Answer 1

sin 18°/cos 72°    = sin (90° - 18°) /cos 72°     = cos 72° /cos 72° = 1(ii) tan 26°/cot 64°    = tan (90° - 36°)/cot 64°    = cot 64°/cot 64° = 1(iii) cos 48° - sin 42°      = cos (90° - 42°) - sin 42°      = sin 42° - sin 42° = 0(iv) cosec 31° - sec 59°     = cosec (90° - 59°) - sec 59°     = sec 59° - sec 59° = 0

Answer 2

Sin(90°-72°)/cos72°+tan(90°-64°)/cot64°

Applying sin(90°-theta)=cos(theta)

And tan(90°-theta)=cot(theta)

Cos72°/cos72°+cot64°/cot64°

This implies

1+1=2

Answer:2