objective: use the unit circle instead of a calculator to evaluating trig functions how is the unit...

Evaluating using the Unit CircleObjective: use the Unit Circle instead of a calculator to evaluating trig functionsHow is the Unit Circle used in place of a calculator?

Remember…

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Ex 1) Evaluating each of the following:

cos(45°)

sin(120°)

Finding tangent

Divide the coordinates (y on top)

Dividing fractions: “Keep, Change, Flip”

Simplify using “Keep, Change, Flip”

a. b.c.

Ex 2) Evaluate each of the following

tan(45°)

tan(120°)

Reciprocal Trig Functions

cscθ =

cotθ =

Reciprocal of “cosine”

Reciprocal of “sine”

Reciprocal of “tangent”

Ex) Evaluate each of the following

sec(45°)

csc(120°)

“Undefined”

What happens when you try to evaluate these functions?

a. tan(90°) b. tan(270°)

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

How many radians is 90 degrees?

MATHO!!

MATHO!!

MATHO!!

How many radians is 360 degrees?

MATHO!!

MATHO!!

MATHO!!

MATHO!!

How many radians is 180°?

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

MATHO!!

How many radians is 270°?