Question

Find the value of ` ( sin 50°)/(cos 40°)+ (cosec 40°)/(sec 50°) - 4 cos 50°   cosec 40 °`

Answer 1

`(sin 50°)/(cos 40 °)+ ( cosec 40° )/( sec 50°) - 4 cos 50°  cosec 40°`

`=(cos (90°- 50°))/(cos 40°) + (sec (90°- 40°))/(sec 50°)- 4 sin (90°-50°)  cosec 40°` 

`=(cos 40° )/( cos 40 °) + ( sec50°)/( sec 50°) - 4 sin 40 ° xx 1/ ( sin 40 °)`

=  1 + 1 - 4

= - 2