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प्रश्न
Prove that `cos 80^@/sin 10^@ + cos 59^@ cosec 31^@ = 2`
उत्तर
Cos 80° = cos (90° - 10°) = sin 10°
`=> sin 10^@/sin 10^@ + sin 31^@ cosec 31^@`
= 1 + 1 = 2 `[∵ sin theta cosec theta = 1]`
Hence proved
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