Use cofunction identities and trig identities to find the indicated trig functions

The video tutorial explains how to solve a trigonometric problem involving the cosine of 60 degrees and the sine of 30 degrees. It introduces the concept of cofunction identities, which state that the cosine of 90 degrees minus an angle is equal to the sine of that angle. The tutorial demonstrates how to apply these identities to find that the cosine of 60 degrees is equal to the sine of 30 degrees, providing a clear method for evaluating trigonometric functions.

Why can't traditional methods be used to relate cosine of 60 degrees and sine of 30 degrees?

• Because they are both acute angles.

• Because they are not the same angle.

• Because they are complementary angles.

• Because they are obtuse angles.

What is a cofunction identity in trigonometry?

• It states that the cosine of 90 degrees minus an angle is equal to the sine of that angle.

• It states that the sine of an angle is equal to the cosine of the same angle.

• It states that the tangent of an angle is equal to the cotangent of the same angle.

• It states that the sine of an angle is equal to the tangent of the same angle.

How can you express the sine of 30 degrees using a cofunction identity?

• As the cosine of 60 degrees.

• As the tangent of 60 degrees.

• As the cosine of 30 degrees.

• As the sine of 60 degrees.

What is the result of applying the cofunction identity to cosine of 60 degrees?

• It equals the tangent of 30 degrees.

• It equals the sine of 60 degrees.

• It equals the sine of 30 degrees.

• It equals the cosine of 30 degrees.

What conclusion can be drawn from the application of cofunction identities in this context?

• Cosine of 60 degrees is less than sine of 30 degrees.

• Cosine of 60 degrees is equal to sine of 30 degrees.

• Cosine of 60 degrees is greater than sine of 30 degrees.

• Cosine of 60 degrees is unrelated to sine of 30 degrees.