Question

    The Value of (sin38˚)/(cos52˚) + (cos12˚)/(sin78˚) - 4cos²60˚ is

    A 1/2 Correct Answer Incorrect Answer
    B -1 Correct Answer Incorrect Answer
    D 1 Correct Answer Incorrect Answer

    Solution

    (sin38˚)/(cos52˚)+ (cos12˚)/(sin78˚)- 4cos²60˚ (cos⁡(90-38)˚)/(cos52˚)+ (sin⁡(90-12)˚)/(sin78˚)- 4cos²60˚ (cos52˚)/(cos52˚)+ (sin78˚)/(sin78˚)- 4cos²60˚ ⇒1 + 1 - 4×(1/2)² ⇒1

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