Understanding 45-45-90 Triangles

The video tutorial explains the properties of a 45-45-90 right triangle, focusing on the trigonometric functions sine, cosine, and tangent for a 45° angle. It introduces the concept of a reference triangle, demonstrates how to calculate these functions, and discusses rationalizing the denominator in trigonometric expressions. The tutorial concludes with a summary of the key points covered.

What is the length of the hypotenuse in a 45-45-90 triangle if each leg is labeled as X?

• 2X

• X√2

• X

• X/2

How do you express the sine of a 45° angle in a 45-45-90 triangle?

• 2

• 1/√2

• 1

• √2/2

What is the cosine of a 45° angle in a 45-45-90 triangle?

• 1

• 1/2

• 1/√2

• √2

What is the tangent of a 45° angle in a 45-45-90 triangle?

• 2

• √2

• 1

• 0

If the opposite and adjacent sides of a 45° angle in a 45-45-90 triangle are equal, what is the tangent value?

• 1/2

• 0

• 1

• √2