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# Factorising Trig Functions Question

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1. 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?

Thanks
Blake
2. What identity do you know that relates cos^2 to sin^2?
3. (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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