Equations Flashcards
1
Q
Sin(A+B)
A
sinAcosB + cosAsinB
2
Q
cos(A+B)
A
cosAcosB - sinAsinB
3
Q
sin2A
A
2sinAcosA
4
Q
cos2A
A
cos^2 A-sin^2 A
2cos^2 A-1
1-2sin^2 A
5
Q
arithmetic series : nth term
A
un = a + (n-1)(d)
6
Q
geometric series : nth term
A
un = (a)(r) ^ (n-1)
7
Q
What are the laws of indices
A
a^x x a^y = a^x+y
a^x ÷ a^y = a^x-y
(a^x)^y = a^xy
8
Q
What are log rules
A
log x + log y =log xy
log x - log y= log x/y
klog x = log (x)^k
9
Q
What’s the conversion of logs to powers
A
x = a^n <-> n = loga x
10
Q
What’s the cosine rule
A
a^2 = b^2 + c^2 - 2cosA
11
Q
What’s the area of a triangle
A
1/2absinC
12
Q
Sec^2 A =?
A
1 + tan^2 A
13
Q
Cosec^2 A =?
A
1+ cot^2 A
14
Q
tan2A =?
A
2tanA / (1 - tan^2 A)
15
Q
A
