Trigonometric Functions

Video: Finding Trigonometric Functions Right Triangle Approach

Video: Finding the Exact Values of the Trig Functions using unit circle

Video: Fundamental  Identities and Periodic Properties of Trig Functions

Examples:

1. Given that \(\sin \theta = \frac{3}{5}\), and \(\theta\) is an acute angle, find the exact value of each of the remaining five trigonometric functions of \(\theta\).   SOLUTION

2. Find the exact value of each expression. Do not use a calculator.  SOLUTION

(a)  \(\displaystyle{\tan 10^\circ -\frac{\sin 10^\circ}{\cos 10^\circ}}\)    (b) \(\displaystyle{\cos^2 \frac{\pi}{5} +\frac{1}{\csc^2 \frac{\pi}{5}}}\)    (c)  \(\displaystyle{\sec^2 40^\circ - \tan^2 40^\circ}\)     (d)  \(\displaystyle{\tan 10^\circ \cos 10^\circ \csc 10^\circ}\)

3. The builder of a parking garage wants to build a ramp that meets the ground at \(30^\circ\). If the horizontal span covers \(30\) feet, how long is the ramp?  SOLUTION

4. Find the exact value of each of the remaining trigonometric functions of \(\theta\) if \(\displaystyle{\sin\theta = \frac{12}{13}} \) and \(\displaystyle{\tan \theta < 0 } \).   SOLUTION

5. Answer the following.   SOLUTION

(a) Given that \(\cos\theta=\dfrac{2}{3}\). Find the exact value of \( \cos\theta + \cos(\theta+2\pi) + \cos(\theta+4\pi)\quad \)

(b) Given that \(\cot\theta= -2\). Find the exact value of \( \cot\theta + \cot(\theta-\pi) + \cot(\theta-2\pi)\quad \)