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a cos x + b sin x = c: general solution or number of solutions

This type of question, asked 5 times: 11 May 2023 S2, 16 May 2023 S1, 13 Apr 2026 S2, 19 Apr 2026 S1, 15 May 2026 S2. All 5 questions below, oldest first.

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  1. Question 1

    11 May 2023 S2

    125
    The general solution of sin⁡x+cos⁡x=1\sin x+\cos x=1 is

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  2. Question 2

    16 May 2023 S1

    109
    The general solution of the equation 3cos⁡θ+sin⁡θ=2\sqrt{3}\cos\theta + \sin\theta = \sqrt{2} is

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  3. Question 3

    13 Apr 2026 S2

    55
    The general solution of cos⁡θ−sin⁡θ=1\cos\theta - \sin\theta = 1 is

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  4. Question 4

    19 Apr 2026 S1

    55
    Let x∈[0,6π]x \in [0, 6\pi] satisfy the equation cos⁡x−sin⁡x=−1\cos x - \sin x = -1. If x=k(π3)x = k\left(\dfrac{\pi}{3}\right) where k∈Nk \in N, then find the number of possible values of kk is .....

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  5. Question 5

    15 May 2026 S2

    53
    If x∈(0,2π)x \in (0, 2\pi) satisfies the equation cos⁡x+sin⁡x=12\cos x + \sin x = \frac{1}{2}, then the sum of all distinct values of tan⁡x\tan x is...

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