Given the right triangle below, evaluate .
Table of contents
- 0. Review of College Algebra4h 43m
- 1. Measuring Angles40m
- 2. Trigonometric Functions on Right Triangles2h 5m
- 3. Unit Circle1h 19m
- 4. Graphing Trigonometric Functions1h 19m
- 5. Inverse Trigonometric Functions and Basic Trigonometric Equations1h 41m
- 6. Trigonometric Identities and More Equations2h 34m
- 7. Non-Right Triangles1h 38m
- 8. Vectors2h 25m
- 9. Polar Equations2h 5m
- 10. Parametric Equations1h 6m
- 11. Graphing Complex Numbers1h 7m
2. Trigonometric Functions on Right Triangles
Trigonometric Functions on Right Triangles
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Given the right triangle below, use the sine function to write a trigonometric expression for the missing angle θ.

A
θ=sin−1(135)
B
θ=sin−1(1312)
C
θ=sin−1(125)
D
θ=sin−1(1213)

1
Identify the sides of the right triangle: the hypotenuse is 13, the opposite side to angle θ is 5, and the adjacent side is 12.
Recall the definition of the sine function in a right triangle: sin(θ) = opposite/hypotenuse.
Substitute the known values into the sine function: sin(θ) = 5/13.
To find the angle θ, use the inverse sine function: θ = sin⁻¹(5/13).
This expression, θ = sin⁻¹(5/13), represents the measure of the angle θ in terms of the sine function.
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Multiple Choice
Trigonometric Functions on Right Triangles practice set
