Questions - The Maths and Science Tutor

(a) Use the identity cos(A + B) = cos A cos B − sin Asin B, to show that cos 2A = 1 − 2 sin2A (2) The curves C 1 and C 2 have equations (b) Show that the x-coordinates of the points where C 1 and C 2 intersect satisfy the equation (3) (c) Express 4cos 2x + 3sin 2x in the form R cos (2x − α), where R > 0 and 0 < α < 90°, giving the value of ................
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