TrigonometryDay 1

Need Class Sets (1/2 set for sleeves) for today:Discovering Trig Ratios, Cannibal Puzzle, Easter Rabbit Puzzle

Warm UpGiven the following triangles, find x. 1. 2. 3.

Solve for the missing variables

4. 5. 6. Simplify

2 12 45x x 1

52

3 8 2

y x

x y

2( 5 3)

X = 13 X = 2 6 2X

X = 15, -3

X = 6 and Y = -2

75

Instructions on Clinometer Assembly

- needs to be ready on Tuesday.

ALL parts must be ready and assembled BEFORE class for credit!

Trig MeasuringExercise / Exploration

Complete on Notebook Paper

Determine the ratios in fraction form and also in decimal form rounded to the nearest ten-thousandth.

Notes 9.1 and 9.2 - Trigonometric Functions

The trigonometric (trig) functions are Sine, Cosine, and Tangent.

These functions can be used to find angle measures,knowing the ratio of the sides

OR length of a side,knowing one side and an angle measure.

They are used only for RIGHT triangles!

Notes 9.1 and 9.2 - Trigonometric Functions

The trigonometric (trig) functions are Sine, Cosine, and Tangent.

These functions can be used to find angle measures,knowing the ratio of the sides

OR length of a side,knowing one side and an angle measure.

They are used only for RIGHT triangles!

These section numbers are for the Prentice Hall Geometry Book. Remember, you have online access to that book. Use it for extra

examples, practice, etc.

The trig functions are: Sin =

Cos =

Tan =

where O = opposite, A = adjacent, and H = hypotenuse

and is an angle measurement.

Opposite O

Hypotenuse H

Adjacent A

Hypotenuse H

Opposite O

Adjacent A

SOH CAH TOATo set up trig ratios, look at the first letter of the trig function you’re trying to evaluate and use SOH CAH TOA to help you set up the ratio!

Want to know how I remember SOH CAH TOA??

SOH CAH TOA

Some Old Hamster Caught Another Hamster Teaching Owls Algebra

Finding Trigonometric Ratios

SOH CAH TOA

Ex 1: tan(B)

Ex 2: tan(D)

5

12

12

5

You try! SOH CAH TOA

Ex 3: sin(D)

Ex 4: cos(D)

Ex 5: cos(B)

12

13

5

13

12

13

Cannibal PuzzlePractice Worksheet

Finding missing side lengths with the Trigonometric Ratios

To solve for missing side lengths, set up the trigonometric ratio, and put the trig function over one, then cross-multiply to solve.

Ex 1: Find y.

SOH CAH TOAEx 2: Find x.

Ex 3: Find x.

You Try: (Remember SOH CAH TOA)Use the trig ratios to find the length of the side labeled

with a variable. All angle measures for these examples are in degrees.

1) 2) 3)

4) 5)

X = 20.8 x = 8.3 x = 17.0

X = 5.5 x = 13.7

You Try!Easter Rabbit Puzzle

Homework

Pg 1 odd and Pg 2 all

Print your notes if you have not yet done so!!!