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Maharashtra State BoardSSC (English Medium) 10th Standard

Prove that: θθθθsin2θcosθ+cosθ=secθ

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Question

Prove that:

`(sin^2θ)/(cosθ) + cosθ = secθ`

Sum
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Solution

LHS = `(sin^2θ)/(cosθ) + cosθ = secθ`

= `(sin^2θ + cos^2θ)/(cosθ)`

= `1/(cosθ)`  ...(sin2θ + cos2θ = 1)

= secθ   ...`(1/cosθ = secθ)`

R.H.S 

LHS = RHS

Hence proved.

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Chapter 6: Trigonometry - Practice Set 6.1 [Page 131]

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