Unit 4: Trigonometry

Determine the height of the balloon

Minds On

Unit 4: Trigonometry

Learning Goal:

I can prove simple trigonometric equations using trig identities.

Lesson 7 – Trigonometric Identities

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Prove that sin2 + cos2 = 1

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Prove that tan

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Identity - an equation that is always true, regardless of the value of the

variable.  Trig Identities - equations that are always true,

regardless of the value of θ.

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Bad News….

There are 5 trigonometric identities that you need to know

Good News….

You already know 3!

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

sin2 + cos2 = 1

tan

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

A common math problem is a proof. This is where you will be asked to prove that a given equation is true. You do this by performing a left side - right side check.

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Prove = Cos

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Prove + Tan =

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Prove (tan θ) (sin θ) + cos θ = sec θ

Unit 4: Trigonometry

Lesson 7 – Trigonometric Identities

Homework

Page 273 #3-9, 17 Test Thursday