| |
Surds
Theory Refresher
Click here for "Live" theory.
A surd is the name given to an
irrational number of the form
 , that is, a square root that cannot be simplified.
The pair of expressions  and 
are called conjugates, that is, each is the conjugate of the
other. Note that when you multiply conjugates together, the result
is a rational number:
Rationalising the Denominator
Rationalising the denominator is the process of removing surds
from the denominator of a fraction.
For fractions with a single surd as a factor on the denominator,
multiply numerator and denominator by the surd.
For fractions with two terms in the denominator, at least one of
which contains a surd, multiply the numerator and denominator by the
conjugate of the denominator.
Notes
Back to the top
|
|
|
| |
