- 0. Functions7h 52m
- Introduction to Functions16m
- Piecewise Functions10m
- Properties of Functions9m
- Common Functions1h 8m
- Transformations5m
- Combining Functions27m
- Exponent rules32m
- Exponential Functions28m
- Logarithmic Functions24m
- Properties of Logarithms34m
- Exponential & Logarithmic Equations35m
- Introduction to Trigonometric Functions38m
- Graphs of Trigonometric Functions44m
- Trigonometric Identities47m
- Inverse Trigonometric Functions48m
- 1. Limits and Continuity2h 2m
- 2. Intro to Derivatives1h 33m
- 3. Techniques of Differentiation3h 18m
- 4. Applications of Derivatives2h 38m
- 5. Graphical Applications of Derivatives6h 2m
- 6. Derivatives of Inverse, Exponential, & Logarithmic Functions2h 37m
- 7. Antiderivatives & Indefinite Integrals1h 26m
- 8. Definite Integrals3h 25m
0. Functions
Introduction to Trigonometric Functions
Problem 68
Textbook Question
In Exercises 65–68, ABC is a right triangle with the right angle at C. The sides opposite angles A, B, and C are a, b, and c, respectively.
a. Express sin A in terms of a and c.
b. Express sin A in terms of b and c.

1
Identify the right triangle ABC with the right angle at C, where sides opposite angles A, B, and C are a, b, and c, respectively.
Recall the definition of the sine function in a right triangle: \( \sin(\theta) = \frac{\text{opposite side}}{\text{hypotenuse}} \).
For part (a), angle A is opposite side a and the hypotenuse is c. Therefore, \( \sin A = \frac{a}{c} \).
For part (b), use the Pythagorean theorem to express a in terms of b and c: \( a = \sqrt{c^2 - b^2} \).
Substitute the expression for a from the Pythagorean theorem into the sine formula: \( \sin A = \frac{\sqrt{c^2 - b^2}}{c} \).
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