After completing this section, students should be able to do the following.

  • Use the Pythagorean Theorem to calculate the side length of a right triangle when given the other two side lengths.
  • State the definition of in the context of a right triangle.
  • Calculate and using a right triangle with angle .
  • State the definition of a radian.
  • Convert between degrees and radians.
  • Use similar triangles to explain why it does not matter which specific right triangle is used to calculate the value of a trigonometric function.
  • Explain how the points of the unit circle correspond to values of by using right triangles with a radius of one.
  • State the definition of in the context of the unit circle.
  • Evaluate the six trigonometric functions at common angles using the unit circle.
  • State the three Pythagorean Identities and their domains.
  • Derive the first Pythagorean Identity using a right triangle, the unit circle, and the Pythagorean Theorem.
  • Identify the domains of inverse trigonometric functions.
  • Use inverse trigonometric functions to solve simple trigonometric equations.