Evaluate the identity using sum and difference formula

The video tutorial guides viewers through solving a trigonometric problem by working with sine and cosine functions. It begins with setting up the problem, identifying variables, and verifying the formula. The instructor uses a unit circle to aid in calculations, ultimately arriving at the solution. The process is explained step-by-step, ensuring clarity and understanding.

What is the first step the teacher suggests in solving the trigonometric problem?

• Identify the variables as sine and cosine.

• Draw a unit circle.

• Calculate the cosine of π/2.

• Verify the formula used.

Why does the teacher emphasize verifying the formula?

• To simplify the trigonometric expression.

• To confirm the calculation of π/2.

• To check the accuracy of the unit circle sketch.

• To ensure the correct variables are used.

What is the cosine of π/2 according to the unit circle?

• 1

• 0

• -1

• Undefined

What is the result of the expression after evaluating cosine of π/2?

• Positive cosine of X

• Negative cosine of X

• Sine of X

• Zero

How does the teacher conclude the problem-solving process?

• By verifying the initial assumption.

• By matching the result with the right side of the equation.

• By recalculating the sine of X.

• By drawing another unit circle.