Question

Arrange the steps in the correct order to express cos3x in terms of cosx

cos(2x)cos(x)-sin(2x)(x)
[1-sin^2(x)]cos(x)-[2sin(x)cos(x)]sin(x)
cos(x)-4sin^2(x)cos(x)
4cos^3(x)-3cos(x)
cos(2x+x)
cos(x){1-4[1-cos^2(x)]}
cos(x)-2sin^2(x)cos(x)-sin^2(x)cos(x)
cos(x)[1-4sin^2(x)]
cos(x)[-3+4cos^2(x)]

Answer 1

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