Trigonometry angles

• Wiskunde
• Middelbare school
• havo
• Leerjaar 3

Trigonometry

You need your notebook, calculator and Ipad

Goals

• I can fiend the adjacent, opposite and the hypothenuse in a triangle
• I can to use trigonometry to find unknown sides and unknown angles in a triangle.

Trigonometry

Trigonometry

Adjacent side:

Opposite side:

Hypothenuse:

Trigonometry

Adjacent side: QR

Opposite side: QS

Hypothenuse: RS

Name the opposite side.

1. KL
2. KM
3. ML

Name the hypotenuse

1. KL
2. KM
3. ML

Name the adjacent side.

1. RS
2. RT
3. ST

Trigonometry

Trigonometry

sin = sinus

cos =  cosinus

tan = tangens

Trigonometry

sin = sine, pronounced sign

cos =  cosine, pronounced co-sign

tan = tangent, pronounced tan-gent

Trigonometry

• Greek letter
• Represents an unknown angle

θ

Trigonometry

SOH, CAH, TOA

 

sin(θ)=​hypotenuse​​opposite​​

cos(θ)=​hypotenuse​​adjacent​​

tan(θ)=​adjacent​​opposite​​

tan(∠B)=...

1. ​17​​8​​
2. ​15​​8​​
3. ​17​​15​​
4. ​8​​15​​

sin(∠B)=...

1. ​61​​11​​
2. ​60​​11​​
3. ​61​​60​​
4. ​11​​60​​

Calculating angles

Calculating angles

tan(∠B)=​a​​o​​

Calculating angles

tan(∠B)=​a​​o​​

tan(∠B)=​8​​15​​

Calculating angles

tan(∠B)=​a​​o​​

tan(∠B)=​8​​15​​

tan(∠B)=1.875

Calculating angles

tan(∠B)=​a​​o​​

tan(∠B)=​8​​15​​

tan(∠B)=1.875

∠B=tan​−1​​(1.875)

Calculating angles

tan(∠B)=​a​​o​​

tan(∠B)=​8​​15​​

tan(∠B)=1.875

∠B=tan​−1​​(1.875)

∠B≈61.92

Calculate ∠B

Calculate ∠B, round to two decimal places

Exercises

• 11.1 Pythagoras (homework)
• 11.2 Soh Cah Toa
• Until 11:20
• Raise your finger if you have any questions or you're done
• Communicate in English please