Upload
duongtruc
View
215
Download
2
Embed Size (px)
Citation preview
Lesson 84 Trigonometry with answers.notebook
1
February 18, 2015
Questions/Main Ideas Lesson 84 Trigonometry
trigonometry from Greek, trigon, meaning triangle, and metron , meaning measure
Trigonometric Ratios
words: sine A =
A
B
C
opposite A
opposite B
measure of leg opposite Ameasure of hypotenuse
sin A = BCAB
sin B = ACAB
words: cosine A =
A
B
C
adjacent to B
adjacent to A
measure of leg adjacent Ameasure of hypotenuse
cos A = ACAB
cos B = BCAB
Questions/Main Ideas
Lesson 84 Trigonometry with answers.notebook
2
February 18, 2015
Questions/Main Ideas
words: tangent A = measure of leg opposite Ameasure of leg adjacent A
A
B
C
adjacent to Band opposite to A
adjacent to Aand opposite B
tan A = BCAC
tan B = ACBC
Questions/Main Ideas mnemonic device
SOH CAH TOAtan = opposite
adjacent
sin = opposite
hypotenuse
cos = adjacent
hypotenuse
Example 1Find sin L, cos L, tan L, sin N, cos N, and tan N. Express each ratio as a fraction and as a decimal.
Lesson 84 Trigonometry with answers.notebook
3
February 18, 2015
Questions/Main Ideas Example 2Use a special right triangle to express the cosine of 60 as a fraction and as a decimal to the nearest hundredth.
Example 3Find each value to the nearest ten thousandth (be sure calculator is in degree mode)
a. tan 56
b. cos 89
Questions/Main Ideas Example 4A fitness trainer sets the incline on a treadmill to 7 degrees. The walking surface is 5 feet long. Approximately how many inches did the trainer raise the end of the treadmill from the floor?
Lesson 84 Trigonometry with answers.notebook
4
February 18, 2015
Questions/Main Ideas Find the measure of an angle by using the inverse of sine, cosine, or tangent.
Lesson 84 Trigonometry with answers.notebook
5
February 18, 2015
Questions/Main Ideas Example 5Use a calculator to find the measure of P to the nearest tenth.
Questions/Main Ideas solving a right triangle finding all of the missing sides and angles
you must know two side lengths orone side length and the measure of one acute angle
Example 6Solve the right triangle. Round side measures to the nearest hundredth and angle measures to the nearest degree.