Finding the Value of Trigonometric Functions Given Information about the Values of Other Trigonometric Functions (6.3.3)

Question 1

• It is possible to find the value of trigonometric functions for an angle θ given only information about other trigonometric
functions for θ. Here is one method of solving these problems:
1. Determine which quadrant θ lies in.
2. Sketch a picture of θ and its right triangle in the x-y plane.
3. Use the Pythagorean theorem to find the length of the unknown side of the triangle.
4. Use the triangle to compute the values of the trigonometric functions.

Answer 1

• It is possible to find the value of trigonometric functions for an angle θ given only information about other trigonometric
functions for θ. Here is one method of solving these problems:
1. Determine which quadrant θ lies in.
2. Sketch a picture of θ and its right triangle in the x-y plane.
3. Use the Pythagorean theorem to find the length of the unknown side of the triangle.
4. Use the triangle to compute the values of the trigonometric functions.