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    If acot θ = b, then what will be the value of b cos θ−a sin θb cos θ+a sin θ\frac{\text{b}\space\text{cos
    Question

    If acot θ = b, then what will be the value of b cos θa sin θb cos θ+a sin θ\frac{\text{b}\space\text{cos}\space\text{θ}-{\text{a}\space\text{sin}\space\text{θ}}}{{\text{b}\space\text{cos}\space\text{θ}+{\text{a}\space\text{sin}\space\text{θ}}}}​ ?

    A.

    0

    B.

    b2+a2\text{b}^2+\text{a}^2​​

    C.

    b2a2b2+a2\frac{\text{b}^2-\text{a}^2}{\text{b}^2+\text{a}^2}​​

    D.

    b2+a2b2a2\frac{\text{b}^2+\text{a}^2}{\text{b}^2-\text{a}^2}​​

    Correct option is C

    Given:

    acot θ = b 

    cot θ = ba\frac ba​​

    Solution:

    b cos θa sin θb cos θ+a sin θ\frac{\text{b}\space\text{cos}\space\text{θ}-{\text{a}\space\text{sin}\space\text{θ}}}{{\text{b}\space\text{cos}\space\text{θ}+{\text{a}\space\text{sin}\space\text{θ}}}}

    bcosθsinθabcosθsinθ+a\frac{\frac{bcos\theta }{sin\theta} -a }{\frac{bcos\theta}{sin\theta}+a}

    =bcotθabcotθ+a\frac{bcot\theta -a }{bcot\theta+a}

    b×baab×ba+a\frac{b\times \frac ba -a }{b\times \frac ba+a}

    b2a2ab2+a2a\frac{\frac{b^2 -a^2}{a}}{\frac{b^2+a^2}{a}} = b2a2b2+a2\frac{b^2 -a^2}{b^2+ a^2}​​

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