Videos and lessons to help High School students learn how to
understand that by similarity, side ratios in right triangles are
properties of the angles in the triangle, leading to definitions
of trigonometric ratios for acute angles.

Common Core: HSG-SRT.C.6

Related Topics:

Common
Core (Geometry)

Common Core
for Mathematics

Preliminary connections between similar triangles and trigonometry.

Trig and similar triangles.

Labeling Sides

Learn how to label the sides of a right triangle as 'hypotenuse', 'opposite', and 'adjacent' in relation to one of the triangle's acute angles.

Writing Trig Ratios

Writing the basic trig ratios given three side lengths; or given two side lengths.

Writing Ratios part 1

Learn how to write the three primary trig. ratios for a right triangle given the three side lengths.

Writing Ratios part 2

Learn how to write the three primary trig. ratios for a right triangle given two of the three side lengths.

Finding a Side Using Trig

Using the tangent function to find an unknown side in a right triangle - two examples... one where the missing side ends up on the top of the ratio in the trig equation, and another where it ends up on the bottom.

Finding an Angle Using Trig

Using the inverse tangent function to find an angle in a right.

Trig Ratios on a Calculator

Introduction to the trig function buttons (SIN,COS,TAN), and inverse function buttons (INVERSE SIN,COS,TAN) on a calculator.

Introduction to Trigonometry

Lesson Objective

Calculate sine, cosine and tangent

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