Trig

Question 1

What is cos^2(x) + sin^2(x) identical to

Answer 1

cos^2(x) + sin^2(x) = 1

Question 2

What is sec^2(x) identical to

Answer 2

1 + tan^2(x)

Question 3

What is 1 identical to with cos and sin

Answer 3

cos^2(x) + sin^2(x)

Question 4

What is 1 + tan^2(x) identical to

Answer 4

sec^2(x)

Question 5

What is 1 + cot^2(x) identical to

Answer 5

cosec^2(x)

Question 6

What is cosec^2(x) identical to

Answer 6

1 + cot^2(x)

Question 7

Double angle formulae for sin

Answer 7

Sin(2x)= 2sin(x)cos(x)

Question 8

Double angle formulae for cos

Answer 8

cos(2x)=cos^2(x)-sin^2(x)

Question 9

sin(A±B) is

Answer 9

sin(A±B)=sinAcosB±cosAsinB

Question 10

cos(A±B) is

Answer 10

cos(A±B)=cosAcosB∓sinAsinB

Question 11

tan(A±B) is

Answer 11

tan(A±B)=tanA±tanB / 1∓tanAtanB

Question 12

What is harmonic form

Answer 12

asinθ+bcosθ=Rsin(θ+α)
or
acosθ+bsinθ=Rcos(θ+α)

Question 13

How do you find R for harmonic form?

Answer 13

R=sqrt(a^2+b^2)

Question 14

how do you find alpha for harmonic form?

Answer 14

a=sin^1(cos coefficient magnitude/ r)
or
a=cos^1(cos coefficient magnitude/ r) if cos is the first value