Section 9.4 Sum to Product & Product to Sum Formulas Video Flashcard

Front

How do you simplify cosine of negative x using the even property of cosine?

Back

Rewrite it as cosine of x.

Front

What is the final simplified form of 2 sine(2x) in the double angle identity?

Back

4 sine(x) cosine(x).

Front

What is the final simplified form of 2 cosine(2x) * sine(x)?

Back

4 sine^2(x) cosine(x).

Front

What is the result of applying the sum-to-product formula to cosine(58) + cosine(12)?

Back

2 cosine(35) cosine(23).

Front

In the example of converting sum to product, what is the result of 2x over 2?

Back

x.

Front

What is the even property of cosine?

Back

Cosine is an even function, meaning cosine(-x) = cosine(x).

Front

What is the double angle identity for sine?

Back

sin(2x) = 2 sin(x) cos(x).

Front

What is the double angle identity for cosine?

Back

cos(2x) = cos^2(x) - sin^2(x).

Front

What is the sum-to-product formula for sine?

Back

sin(a) + sin(b) = 2 sin((a+b)/2) cos((a-b)/2).

Front

What is the sum-to-product formula for cosine?

Back

cos(a) + cos(b) = 2 cos((a+b)/2) cos((a-b)/2).