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˚ (sin⁡(90-52)˚)/(cos52˚)+ (cos⁡(90-78)˚)/(sin78˚)- 4cos²60˚ (cos52˚)/(cos52˚)+ (sin78˚)/(sin78˚)- 4cos²60˚ ⇒1 + 1 - 4×(1/2)² ⇒1

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