Unit 4: Trigonometry

Minds On

Determine the EXACT value of:

a) Tan 150 b) Csc 225

Unit 4: Trigonometry

Minds OnPoint (3, -3) is on the terminal arm of an angle:a) Determine the primary trig ratios and reciprocal trig ratiosb) Determine the Related Acute Angle (c) Determine the Principal Angle (d) Determine another angle between 0 and 360 that has the same trig ratios for Tan.

Unit 4: Trigonometry

Learning Goal:

I can prove simple trigonometric equations using trig identities.

Lesson 5 – Trigonometric Identities

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

Prove that sin2 + cos2 = 1

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

Prove that tan

Unit 4: Trigonometry

Lesson 5 – 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 5 – Trigonometric Identities

Bad News….

There are 8 trigonometric identities that you need to know

Good News….

You already know 6!

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

sin2 + cos2 = 1

tan

Unit 4: Trigonometry

Lesson 5 – 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 5 – Trigonometric Identities

Prove = Cos

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

Prove + Tan =

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

Prove (tan θ) (sin θ) + cos θ = sec θ

Unit 4: Trigonometry

Lesson 5 – Trigonometric Identities

Homework

Pg. 310 #1, 3, 5, 6, 8, 12 Quiz Tomorrow