Unit 5: Introduction to Trigonometry Lesson 5: Evaluate Trig Functions Accel Precalc Unit 5: Introduction to Trigonometry Lesson 5: Evaluate Trig Functions EQ: How do you evaluate trig functions of angles not found on special triangles?

Check MODE of calculator before you evaluate any function. Using a Graphing Calculator to Approximate the Ratio of All Six Trig Functions: Check MODE of calculator before you evaluate any function. Degrees or Radians

Ex. Evaluate each trig function to four decimal places.

These are the reciprocals of the ratio not the angle. What about the reciprocal functions? Recall: These are the reciprocals of the ratio not the angle. NOTE: DO NOT USE THE SIN-1, COS-1, or TAN-1 KEYS!!

Ex. Evaluate each trig function to four decimal places. You want the reciprocal of the RATIO, not the ANGLE!

Using a Graphing Calculator to Approximate an Angle for All Six Trig Functions: Up to this point, you have been given the angle and have found the ratio. Now you will be given the ratio and will find the angle.

How do you solve algebra equations? RECALL: How do you solve algebra equations? You used inverse operations to solve these equations. When solving for angles in trig, you need to use inverse trig functions.

Recall: What is function notation? What is inverse function notation? Inverse Notation for Trig Functions:

sin 60 = _____ Given angle, asks for a RATIO Given ratio, asks for a ANGLE Use an inverse trig function to solve. Respond in degrees.

Ex. Evaluate. Round to nearest hundredth of a degree.

NOTE: Reciprocal of RATIO, not ANGLE. Ex. Evaluate. State angle in degrees and minutes. NOTE: Reciprocal of RATIO, not ANGLE.

NOTE: Reciprocal of RATIO, not ANGLE. Ex. Evaluate. State angle in radians. NOTE: Reciprocal of RATIO, not ANGLE.

In Class Assignment: Complete Calculator Worksheet Parts I – VI Textbook p. 311-312 ODDS #39 – 45, 53, 55