maths-urgently needed

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the general solution of
sin x + sin 2x + sin 3x + sin 4x = 0 ?

  • maths-urgently needed -

    obviously any multiple of pi/2 will work
    Also, since
    sin pi/5 = sin 4pi/5 = 1/√8 (5-√5)
    sin 2pi/5 = sin 3pi/5 = 1/√8 (5+√5)

    any multiple of pi/5 will also work.

    So,

    x = pi(n/2)
    x = pi(2n/5)

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