Trigonometry 4 Flashcards
1
Q
Sin 2x
A
2 Sin x . Cos x
2
Q
Cos 2x
A
Cos^2x - Sin^2x
3
Q
Tan 2x
A
2 Tan^2x / 1 - Tan x
4
Q
Sin x + Sin y
A
2 Sin [ x+y/2 ] Cos [ x-y/2 ]
5
Q
Cos x + Cos y
A
2 Cos [ x+y/2 ] Cos [ x-y/2 ]
6
Q
Cos x - Cos y
A
-2 Sin [ x+y/2 ] Sin [ x-y/2 ]
7
Q
Sin^-1 [-x]
A
-Sin^-1 [x]
8
Q
Tan^-1 [-x]
A
-Tan^-1 [x]
9
Q
Cosec^-1 [-x]
A
-Cosec^-1 [x]
10
Q
Cos^-1 [-x]
A
Pi - Cos^-1 [x]
11
Q
Sec^-1 [-x]
A
Pi - Sec^-1 [x]
12
Q
Cot^-1 [-x]
A
Pi - Cot^-1 [x]
