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Factorising Trig Functions Question

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    • Thread Starter

    Hi guys,

    I'm working through an exercise in Core 3 and I'm a bit stumped

    The question says Factorise the expression 3x^3 - 10x^2 + 9x -2
    And so I did that to get (3x-1)(x-2)(x-1)
    It then says Hence solve the following equation for -180</= q </=180
    3sin^3 q + 10cos^2 q + 9sinq - 12 = 0

    I would normally be okay if it was just involving sin but here there is a cos too. Any advice on how to go about this?


    What identity do you know that relates cos^2 to sin^2?
    • Thread Starter

    (Original post by Elzar)
    What identity do you know that relates cos^2 to sin^2?
    Oh! Cos^2 + Sin^2 = 1
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