Question

sin50/cos40 + cosec70/sec20 - 2cos70cosec20 = 0​

Answer 1

Answer:

LHS : sin50/cos40 + cosec70/sec20-2cos70cosec20

= sin(90-40)/cos40 + cosec70/sec(90-70)-2cos70*1/sin20

= cos40/cos40 + cosec70/cosec70-2cos 70/sin(90-70)

= 1 + 1 - 2cos70/sin70

=2-2

=0

= RHS