### All Trigonometry Resources

## Example Questions

### Example Question #1 : Sum And Difference Of Sines And Cosines

What is the correct formula for the sum of two sines: ?

**Possible Answers:**

**Correct answer:**

This is a known trigonometry identity. Whenever you are adding two sine functions, you can plug and into the formula to solve for this sum

### Example Question #2 : Sum And Difference Of Sines And Cosines

Solve for the following given that . Use the formula for the sum of two sines.

**Possible Answers:**

**Correct answer:**

We begin by considering our formula for the sum of two sines

We will let and and plug these values into our formula.

### Example Question #3 : Sum And Difference Of Sines And Cosines

Solve for the following using the formula for the differences of two cosines. Do not simplify.

**Possible Answers:**

**Correct answer:**

We begin by considering the formula for the differences of two cosines.

We will let and . Proceed by plugging these values into the formula.

### Example Question #4 : Sum And Difference Of Sines And Cosines

Which of the following completes the identity

**Possible Answers:**

**Correct answer:**

This is a known trigonometry identity and has been proven to be true. It is often helpful to solve for the quantity within a cosine function when there are unknowns or if the quantity needs to be simplified

### Example Question #5 : Sum And Difference Of Sines And Cosines

Solve for the following using the correct identity:

**Possible Answers:**

**Correct answer:**

To solve this problem we must use the identity

. We will let and .

### Example Question #6 : Sum And Difference Of Sines And Cosines

True or False: To solve for a problem in the form of , I use the identity .

**Possible Answers:**

False

True

**Correct answer:**

False

This answer is false. is not the same as .

For example, say and

And so the correct identity to use for this is

### Example Question #7 : Sum And Difference Of Sines And Cosines

Solve for the following using the correct identity:

**Possible Answers:**

**Correct answer:**

The correct identity to use for this kind of problem is

. We will let and .

### Example Question #8 : Sum And Difference Of Sines And Cosines

Which of the following is the correct to complete the following identity: ___?

**Possible Answers:**

**Correct answer:**

This is a known trigonometry identity and has been proven to be true. It is often helpful to solve for the quantity within a cosine function when there are unknowns or if the quantity needs to be simplified

Certified Tutor

Certified Tutor