Question

    If sin A - cos A = 3/7, then find value of sinA + cos B,  where A is an acute angle.

    A √94/5 Correct Answer Incorrect Answer
    B 1 Correct Answer Incorrect Answer
    C √89/7 Correct Answer Incorrect Answer
    D 9/16 Correct Answer Incorrect Answer

    Solution

    We Know that, (a+b)2 + (a-b)2 = 2(a2 + b2) Hence, (sin A + cos A)2 + = 2(sin2 A + cos2 A) => (sin A + cos A)2 +   = 2(1) => (sin A + cos A)2  = 2 -  => (sin A + cos A)2  = 2 - = = => (sin A + cos A) =

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