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