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Sin theta + cos theta is equal to cosec theta prove LHS and RHS equal |
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Answer» ong>ANSWER: We have to prove that cot+cosecθ sinθ =2+ cotθ−cosecθ sinθ or, cotθ+cosecθ sinθ − cotθ−cosecθ sinθ =2
Now,
⇒ LHS = cotθ+cosecθ sinθ − cotθ−cosecθ sinθ
⇒ LHS = cosecθ+cotθ sinθ + cosecθ−cotθ sinθ
⇒ LHS = sinθ{ cosecθ+cotθ 1 + cosecθ−cotθ 1 }
⇒ LHS = $$sin \, \theta\left\{\dfrac{cosec \, \theta \, - \, cot \, \theta \, + \, cosec \, \theta \, + \, cot \, \theta}{cosec^2 \, \theta \, - \, cot^ \, \theta}\right\} \, = \, sin \, \theta \, \left(\dfrac{2 \, cosec \, \theta}{1} \right)$$
⇒ LHS = sinθ(2cosecθ)=2sinθ× sinθ 1 =2=RHS
⇒ LHS = 2 = RHS
ALTERNANATIVELY,
LHS = cotθ+cosecθ sinθ
⇒LHS=sinθ(cosecθ−cotθ) [∵ cosecθ+cotθ 1 =cosecθ−cotθ]
⇒ LHS = sinθ( sinθ 1 − sinθ cosθ )=sinθ( sinθ 1−cosθ )
⇒ LHS = 1 - COS θ
⇒ = 2 - (1 + cos θ)
⇒ LHS = 2 - 1−cosθ (1+cosθ)(1−cosθ)
⇒ LHS = 2 - 1−cosθ (1−cos 2 θ)
⇒ LHS = 2 - 1−cosθ sin 2 θ =2− sinθ 1−cosθ
sinθ =2− sinθ 1 − sinθ cosθ
sinθ
⇒ LHS = 2 - cosecθ−cotθ sinθ = RHS Hope it help's you Drop some Thanks Mark as Brainliest |
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