Exploring the Unit Circle and Trigonometric Functions

Mr. Tarrou explains the unit circle, focusing on its definition, trigonometric functions, and the use of special triangles. He covers angles in degrees and radians, and how to determine coordinates using reference angles. The video also discusses the significance of quadrants and sign changes in the unit circle.

What is the radius of the unit circle?

• 2

• 1

• 0.5

• 3

Which trigonometric function is represented as y over r in the unit circle?

• Cotangent

• Tangent

• Cosine

• Sine

For a 45-45 triangle, what is the length of each leg after adjusting for the unit circle?

• 1

• 2

• square root of 2 over 2

• 0.5

Which triangle is used to derive values for the unit circle?

• Isosceles triangle

• 30-60-90 triangle

• Right triangle

• Equilateral triangle

How many degrees are there between each major angle marked on the unit circle?

• 45 degrees

• 90 degrees

• 60 degrees

• 30 degrees

What is the cosine value at 0 degrees in the unit circle?

• 0

• -1

• 1

• 0.5

What is the sine of 90 degrees in the unit circle?

• 0

• -1

• 1

• 0.5

What is the cosine of 180 degrees in the unit circle?

• 0.5

• 0

• 1

• -1

What is the sine value at 30 degrees in the unit circle?

• square root of 3 over 2

• 0.5

• 0

• 1

At what angle do the coordinates start to repeat due to sign changes?

• 45 degrees

• 90 degrees

• 360 degrees

• 180 degrees