Composition of inverses using a triangle with variables

The video tutorial explains the concept of the unit circle, focusing on creating triangles and understanding the sine function. It highlights the importance of the hypotenuse being one in the unit circle, simplifying calculations. The Pythagorean theorem is used to find missing values, and the cosine function is calculated using the adjacent side. The tutorial emphasizes the relationship between the unit circle and trigonometric functions.

What is the hypotenuse of a triangle on the unit circle?

• It varies depending on the triangle

• It is always equal to the Y coordinate

• It is always equal to 1

• It is always equal to the X coordinate

How is the sine of an angle represented on the unit circle?

• As the Y coordinate

• As the adjacent side

• As the hypotenuse

• As the X coordinate

Which theorem is used to find the missing side of a triangle in this context?

• Pythagorean theorem

• Sine rule

• Cosine rule

• Tangent rule

What is the expression for the missing side 'b' in terms of X?

• b = 4X^2 - 1

• b = 1 - 4X^2

• b = sqrt(1 - 4X^2)

• b = sqrt(1 + 4X^2)

How is the cosine of the function determined when the hypotenuse is 1?

• By taking the Y coordinate

• By taking the adjacent side

• By using the Pythagorean theorem

• By dividing the opposite side by the hypotenuse