Warm-Up 2/12 Evaluate – this is unit circle stuff, draw your triangle.

7.1 Basic Trigonometric Identities Trig Identity: a trig expression that is true for all values of the variables Reciprocal Identities

Quotient Identities Pythagorean Identities This is the most basic all are derived from it. Divide everything by cos 2  Divide everything by sin 2 

Opposite angle Identities

Examples Use the given info to find the trig value. 1. If, find Since and are reciprocals,

2. If use the identities to find tan  Use an identity that involves given info. Substitute what you know. Move the 1 to the right side. Change it to 9/9. Then

Express each value as a trigonometric function of an angle in Quadrant I. 3. Draw everything you know. Then draw the same reference angle in the first quadrant. Sine is ____________ in the 3 rd quadrant So If I have to write it as an angle in the 1 st quadrant will it be the same or will I have to take the opposite? Take the opposite, so your final answer is negative -sin60 o If the original problem is in radians your final answer must be in radians, if it is degrees, your final answer will be in degrees Subtract 360 or 2  if in radians

Try these: Check: If the original problem is in radians your final answer must be in radians, if it is degrees, your final answer will be in degrees.

Simplify Is there a GCF? Yes sinx Factor Use your identities, look back at your notes 1+cot 2 x = csc 2 x Write csc x in terms of sin x, Simplify completely done

7.1 Assignment p. 428 # 25 – 35, 45 – 53 odds Must use the identities for #