Trig P4

Question 1

Addition Formulae - What is Sin(A +/- B)

Answer 1

SinACosB +/- CosASinB

Question 2

Addition Formulae - What is Cos(A +/- B)

Answer 2

CosACosB -/+ SinASinB

Question 3

Addition Formulae - What is Tan(A +/- B)

Answer 3

(tanA +/- tanB) / (1 -/+ tanAtanB)

Question 4

Double angle formulae - What does Sin2A equal? (1, /2, x3, 2A=4A, 2A=60)

Answer 4

1 = 2SinACosA
/2 = 1/2Sin2A = SinACosA
x3 = 3Sin2A = 6SinACosA
2A=4A = Sin4A = 2Sin2ACos2A
2A=60 = Sin60 = 2Sin30Cos30

Question 5

Double angle formulae - What does Cos2A equal?

Answer 5

Cos^2A-Sin^2A

Question 6

Double angle formulae - What does Tan2A equal? (1, /2, x2, 2A=A, 2A=60)

Answer 6

1 = 2TanA / 1-Tan^2A
/2 = 1/2Tan2A = TanA / 1-Tan^A
x2 = 2Tan2A = 4TanA/1-Tan^2A
2A=A = TanA = 2Tan(A/2)/1-Tan^2(A/2)
2A=60 = Tan60 = 2Tan(30)/1-Tan^2(30)