Week 12

This week we continued to look at Trig Functions but we looked at how to Verify Identities.

There are five suggestions on how to Verify.

1. simplify the more complicated side

2. Find common denominators

3. change all trig functions in  terms of sine and cosine

4. use an identity

5. multiply by a conjugate pair.

*You can only work on one side of the equation. 

There are many fundemental identities. Some we already looked at.

Above are the identities used to verify equations and more. 

FIrst thing you do is you choose one side of the equation.

For example:

sinθcosθ=1/tanθ+cotθ

You could pick the right or the left. I’d pick the left. You first try to turn tangent and cotangent into sine and cosine . You use the identity sinx/cosx and cosx/sinx. You then solve all the way to make it equal to the other side. Sinθcosθ. When you’ve reached that. You know you’re done. You can say you verified then.

Below is another example.

This is what we did to verify identities.

We then looked at Sum and DIfference Formulas and many others. 

Below are the some identites used to find the answer to solving and finding the number of an equation.

To use a Sum and Difference formula. 

Ex: cos 7π/12

1. First you find the degree of that which is 105°. 

2. You find which sum and difference formula should be used.

3. Find the number degrees you want to equal up to 105

4. You put the numbers into the equation.

5. Simplify to the simplist form.

6. Thats the answer

The same can be said for the others as well for a double angle and a half angle.

Below are examples of double angle and half angle equations.

This is what we did this week. We looked at Verifying and Sum and Difference Formulas.

SEE YOU NEXT WEEK!!!