Trigonometric Ratios Geometry

Click here to find out What is trigonometry?

Things to know The following sides are labeled in regards to the angle . It is important to know that the location of the opposite and adjacent sides will change (depending on the angle), but the hypotenuse will always be the same!

TRIGONOMETRIC RATIO A trig ratio is a ratio of the lengths of two sides of a right triangle. There are three basic trig ratios: sine cosine tangent sin cos tan

Trig Ratios Trigonometric ratios are frequently expressed as decimal approximations. You should round the trig ratio to the ten-thousandths place.

What are the 3 trig ratios?

SINE

COSINE

TANGENT

Find sin, cos, and tan of A A z x B C y

Example Compare the sine, the cosine, and the tangent ratios for angle A in each triangle below. B B 13 5 6.5 2.5 C 12 A C 6 A

Example Find the sine, the cosine, and the tangent of angle D and angle E. E 50 14 F 48 D

Use A Calculator Use a calculator to approximate the sine, cosine, and tangent of 82 degrees.

Use a Calculator Use a calculator to approximate the sine, cosine, and tangent of 54 degrees.

Sin and Cos must always be less than 1!! Note: Sin and Cos must always be less than 1!!