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If Sec θ + Tan θ = X, Write the Value of Sec θ − Tan θ in Terms of X. - Mathematics

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Question

If sec θ + tan θ = x, write the value of sec θ − tan θ in terms of x.

Answer in Brief
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Solution

Given:` secθ+tanθ=x` 

We know that, 

`Sec^2θ-tan^2θ=1` 

Therefore, 

`sec^2 θ-tan^2θ=1` 

⇒` (Secθ+tan θ) (Secθ-tan θ)=1` 

⇒` x (secθ-tan θ )=1` 

⇒ `(sec θ-tan θ)=1/x` 

Hence, `sec θ-tan θ=1/4`

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Chapter 11: Trigonometric Identities - Exercise 11.3 [Page 55]

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RD Sharma Mathematics [English] Class 10
Chapter 11 Trigonometric Identities
Exercise 11.3 | Q 5 | Page 55

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Which of the following is valid?


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