Trigonometric Expressions test questions

1

What is the exact value of \(\sin 75^\circ\)?

2

What is the exact value of \(\cos105^\circ\)?

3

Given that \(a\) is an acute angle and that \(\tan a= \frac{1}{5}\), what is the exact value of \(\sin 2a\)?

4

When \(\sin (x + 2y)\cos (y - x) + \cos (x + 2y)\sin (y - x)\) is simplified, what does it equal?

5

When \(\cos 7x^\circ \cos 5x^\circ + \sin 7x^\circ \sin 5x^\circ\) is simplified, what is the answer?

6

If \(\sin x = \frac{2}{3}\) and \(0 \textless x \textless \frac{\pi }{2}\), find the exact values of \(\cos x\) and \(\tan x\).

7

When \(\cos x + \sqrt 3 \sin x\) is expressed in the form \(k\sin (x + \alpha )\), what are the values of \(k\) and \(\alpha\)?

8

The maximum value of \(5\sin (x - 30)^\circ\) occurs where \(x\) equals:

9

What is the maximum value of \(2 + 3\sin (x + 20)^\circ\)?

10

Given that \(k\cos \alpha = - 1\) and \(k\sin \alpha = 1\), \(k \textgreater 0;\,0 \le \alpha \le 360\), what are the values of \(k\) and \(\alpha\)?