Given any expression of the form \(a\cos x + b\sin x\) it is better to rewrite it into one of the forms \(k\cos (x \pm \alpha )\) or \(k\sin (x \pm \alpha )\) before answering the question.

If in doubt, \(k\cos (x - \alpha )\) usually works. These worked examples show the processes you'll need to go through to rewrite an expression in this form. Write \(2\sin x^\circ + 5\cos x^\circ ...