Surds and Indices
Surds and Indices
Indices:
a^m * a^n = a^(m+n)
a^m / a^n = a^(m-n)
(a^m)^n = a^(mn)
(ab)^n = a^n b^n
a^0 = 1
a^-n = 1/a^n
Surds:
sqrt(ab) = sqrt(a)*sqrt(b)
sqrt(a/b) = sqrt(a)/sqrt(b)
Rationalization:
1/(a + sqrt(b)) = (a - sqrt(b))/(a^2 - b)
Useful squares:
| n | n^2 | n | n^2 |
|---|---|---|---|
| 11 | 121 | 21 | 441 |
| 12 | 144 | 22 | 484 |
| 13 | 169 | 23 | 529 |
| 14 | 196 | 24 | 576 |
| 15 | 225 | 25 | 625 |
| 16 | 256 | 26 | 676 |
| 17 | 289 | 27 | 729 |
| 18 | 324 | 28 | 784 |
| 19 | 361 | 29 | 841 |
| 20 | 400 | 30 | 900 |