9. Radians and the Trigonometric Ratios
In this section we see examples of how to use radians instead of degrees when finding the values of sin, cos, tan, csc, sec and cot of angles.
We are using all that we have learned in this chapter. If you are lost:
- Go back and review this Trigonometric Functions chapter.
- See this simple introduction to radians with an interactive graph.
Examples Involving the Trig Functions
Find the value of
2. `sec\ 4.5`
3. `sec\ 4.5^"o"`
Now it's your turn to try the following exercises.
1. Find `tan((4pi)/3)`
2. Find `sin 2.34`
3. Find `θ` if `cos θ = -0.9135 (0 ≤ θ < 2π)`
4. Find `θ` if `csc θ = 3.940\ (0 ≤ θ < 2π)`
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Trigonometry Lessons on DVD
Easy to understand trigonometry lessons on DVD. See samples before you commit.
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