120 likes | 361 Views
Trig. Functions & the Unit Circle. Trigonometry & the Unit Circle. If s a real number and P = ( x,y ) is a point on the unit circle that corresponds to , then: `. VERY important Trig. Identity. What is the Unit Circle?. A circle with radius 1, centered at the origin (0,0)
E N D
Trigonometry & the Unit Circle If s a real number and P = (x,y) is a point on the unit circle that corresponds to , then: ` VERY important Trig. Identity
What is the Unit Circle? • A circle with radius 1, centered at the origin (0,0) • Used to find the trigonometric ratios of each of any angle that is a multiple of 30 or 45.
Filling out unit circle Activity! • Create a 45-45-90 triangle with hypotenuse 1 • Create a 30-60-90 triangle with hypotenuse 1 • Label the lengths of each side • Use these triangles to find the x-y coordinate of each angle’s point of intersection with the unit circle.
The 30-60-90 Triangle 60 1 30
Signs of Trig. Functions on Unit Circle All Sine Tangent Cosine Where are the trig. functions positive?
Also true for Reciprocal Identities!!! All Students Take Calculus
Example 1– Evaluate the Trig. Functions NO CALCULATOR -1 0 DNE 0
Example 2 – Find Trig. Functions Using a Point on the Unit Circle • A point P(x,y) is shown on the unit circle. Find the values of the six trigonometric functions. a. b.
Homework (Due Monday) • Workbook p. 73: 21-26 • Study for Monday’s Unit Circle Quiz!!!