Question

    If X = 15°, find the value of: sin²(3X) +

    cos²(4X) - tan²(2X)
    A 5/12 Correct Answer Incorrect Answer
    B 1/2 Correct Answer Incorrect Answer
    C 3/4 Correct Answer Incorrect Answer
    D 7/12 Correct Answer Incorrect Answer

    Solution

    = sin²(45°) + cos²(60°) - tan²(30°)
    = (1/√2)² + (1/2)² - (1/√3)²
    = 1/2 + 1/4 - 1/3 = 5/12

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