New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    Simplify (cos13°+sin 13°)

    /(cos13°-sin13°)
    A tan (58°) Correct Answer Incorrect Answer
    B tan (58°) Correct Answer Incorrect Answer
    C cos (26°) Correct Answer Incorrect Answer
    D tan (32°) Correct Answer Incorrect Answer

    Solution

    (cos13°+sin 13°) /(cos13°-sin13°) [(cos13°+sin 13°)/cos13°] /[(cos13°-sin13°)/cos13°] =(1+tan13°)/ (1-tan13°)         Put tan 45° in place of 1. =(tan45°+tan13°)/(1-tan13°×tan45°) Using the tangent addition formula:   tan(a+b) =(tanA+tanB)/ (1-tanA.tanB) =tan (45°+13°) =tan (58°)

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