When given a point, how to find the triangle to evaluate for the 6 trig functions

The video tutorial discusses evaluating trigonometric functions without a triangle by using reference angles. It explains the concept of reference angles, how to create right triangles from them, and how to evaluate trigonometric functions using these triangles. The tutorial also covers the calculation of sine, cosine, and tangent, and their reciprocals, using given points and reference angles.

Why can't trigonometric functions be used directly when there is no right triangle?

• Because trigonometric functions require a reference angle.

• Because trigonometric functions require a terminal side.

• Because trigonometric functions are only defined for right triangles.

• Because trigonometric functions need a hypotenuse.

What is a reference angle?

• An angle that is always negative.

• An angle that is equal to the original angle.

• A positive angle from the x-axis to the terminal side.

• An angle that is always greater than 90 degrees.

How can reference angles help in creating a right triangle?

• By using the reference angle to draw a perpendicular line to the x-axis.

• By using the reference angle to determine the sine value.

• By using the reference angle to calculate the tangent.

• By using the reference angle to find the hypotenuse.

What is the sine of Theta if the opposite side is 2 and the hypotenuse is sqrt(5)?

• 2 / sqrt(5)

• 2 / 5

• sqrt(5) / 2

• 1 / sqrt(5)

What is the cotangent of Theta if the opposite side is 2 and the adjacent side is -1?

• 1/2

• -2

• 2

• -1/2