Question

cos 10 cosec80 + sin20 sec70 =​

Answer 1

Answer:

Cos(90-80)×cosec80+sin(90-70)×sec70

=sin80×cosec80+ cos70×sec70

(upper photo)

=1+1

=2

Answer 2

$cos 10 \times cosec80 + sin20 \times sec70 \\ = cos \: 10 \times cosec \: (90 - 10) + sin \: 20 \times sec(90 - 20) \\ = cos \: 10 \times \: sec \: 10 + \: sin \: 20 \times cosec \: 20 \\ = 1 + 1 \\ = 2$