5.5

Double-Angle Formulas

Power-Reducing Formulas

Half-Angle Formula

Product-to-sum Formula

sum-to-product formulas

5.4

Sum and Difference Formulas

cos75 = cos(30 + 45)

= cos30cos45 - sin30sin45

= .259

#Ch5Struggz

I can't find Mr. Wilhelm's post about the chapter for us to comment on so I think we should just post what you think is the hardest or comment on one of the posts already there.

Chapter 5

I believe the hardest part of chapter 5 is incorporating all of the trigonometric identities and figuring out which is the best identity to use for a certain problem or equation. In addition, I find the double angle and half angle identities challenging.

My feelings about Chapter 5

I find the hardest part about Chapter 5, is shifting to a whole new frame of mind in thinking about math in terms of trigonometric functions.  If the functions are in front of you it is not that much harder than algebra.

Solving Trigonometric Equations

Solving Trigonometric Equations

Trigonometric Equations Involving Powers

Solution:

Solving Quadradic Equations using Factoring

Solution:

Using Identites in Equations

Solution:

Using Quadratic Equation

Solution: Since there are two trig functions in this problem, we need to use an identity
to eliminate one of them.

*Make sure to check for extraneous solutions when you square both sides or there is a denominator

Using Fundamental Identities

Reciprocal Identities:

Quotient Identities:

Pythagorean Identities:

Even Identities:

Odd Identities:

Cofunction Identities:

In Chapter 5 section 1 we practice using identites to evaluate a function and simplifying trigonometric expressions. We do this by using the fundamental identities to re-write half of the equation until it matches the other side of the equation.