cos theta - sin theta +1/ sin theta +cos theta -1 =1/cosec theta - cot theta. Step by step explaination no short cut
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Step-by-step explanation:
Cosθ - Sinθ + 1 / Sinθ+Cosθ - 1
//Multiply and divide by Sinθ+Cosθ+1
=> [Cosθ - Sinθ + 1 / Sinθ+Cosθ - 1] * [Sinθ+Cosθ+1/Sinθ+Cosθ + 1]
=> (1 + Cosθ - Sinθ)(1 + Cosθ + Sinθ) / (Sinθ+Cosθ)² - 1
=> (1 + Cosθ)² - Sin²θ / (Sinθ+Cosθ)² - 1
=> 1 + Cos²θ + 2Cosθ - Sin²θ / Sin²θ + Cos²θ + 2SinθCosθ - 1
=> 2Cos²θ + 2Cosθ / 2SinθCosθ (∵ Sin²θ + Cos²θ = 1)
=> 2Cosθ(Cosθ + 1) / 2SinθCosθ
=> Cosθ + 1 / Sinθ
= Cosecθ + Cotθ
//Multiply and divide by Cosecθ - Cotθ
= Cosecθ + Cotθ * [Cosecθ - Cotθ / Cosecθ - Cotθ]
= Cosec²θ - Cot²θ / Cosecθ - Cotθ
= 1/Cosecθ - Cotθ ( ∵Cosec²θ - Cot²θ = 1)
= R.H.S
Hence Proved.
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