Chapter 7 - Trigonometry & Modelling Flashcards
1
Q
Sin (A + B)
A
sin A cos B + cos A sin B
2
Q
sin (A - B)
A
sin A cos B - cos A sin B
3
Q
cos (A + B)
A
cos A cos B - sin A sin B
4
Q
cos (A - B)
A
cos A cos B + sin A sin B
5
Q
tan (A + B)
A
tan A + tan B
1 - tan A tan B
6
Q
tan (A - B)
A
tan A - tan B
1 + tan A tan B
7
Q
sin 2A
A
2 sin A cos A
8
Q
cos 2A
A
cos2A - sin2A
or
2cos2A - 1
or
1 - 2sin2A
9
Q
tan 2A
A
2 tan A
1 - tan2A
10
Q
How do you express a sin x +/- b cos x as Rsin(x +/- β)?
A
- set a = R cos β
- set b = R sin β
- and R = sq root (a2 + b2)
11
Q
How do you express
a cos x +/- b sin x
in the form R cos (x +/- β)?
A
- set a = R cos β
- set b = R sin β
- and R = sq root (a2 + b2)
12
Q
A
