## Pythagorean Identities

#### Aligned To Common Core Standard:

**High School Functions** - HSF-TF.C.8

What Are Pythagorean Identities?
Pythagorean identities are the true representation of Pythagoras theorem as functions. So, these identities can also help us in deciding fundamentally deciding the relationship between sine, cos and tan trigonometric functions.
You can determine from that point the functions of other identities in our lives and how they can make things easy and simple too.
Pythagorean identities are trigonometric identities, which are extensions of the Pythagorean theorem. The fundamental identities state that for every angle: sin^{2} Θ + cos^{2} Θ = 1
Pythagorean identities are extremely useful for simplifying trigonometric expressions, particularly in writing expressions as functions of either sine or cos in the statements of double angle formulas.
There are there Pythagorean identities that you need to recall immediately. The first one is already mentioned above. The rest of the two are:
1 + cot^{2} Θ = csc^{2} Θ and 1 + tan^{2} Θ = sec^{2} Θ Students can use these worksheets and lessons to learn techniques that help them determine missing value in trig. functions.

### Printable Worksheets And Lessons

- Simplifying Problems Step-by-Step Lesson- These problems require you to combine trigonometric identities that many people find difficult.
- Guided Lesson - When you first look at these problems, it blows your mind that the could possibly be equal.
- Guided Lesson Explanation - Don't forget about the use of reciprocals in this problem set.
- Practice Worksheet - These are actually much easier than the lesson based problems.
- Matching Worksheet - I like to use this sheet for a super quick review.