Algebra Review
A few basic facts you will need to remember
but
and
are undefined
and does not
factor
for example do not factor.
![]()
always has one real
solution whether a is positive or negative.
![]()
![]()
, ![]()
Quadratic Formula:
The solution(s) to
are ![]()
and
![]()
Exponents:
for x not 0,
,
![]()
![]()
, 
, ![]()
Cancellation: Only cancel common factors, not summands.
Ex.
x is not a factor
of the numerator and cannot be cancelled.
x + 2 is not a
factor of the denominator and cannot be cancelled.
for ![]()
Miscellaneous problems you will see again in similar form:![]()
Collect terms and factor
. Each summand
contains
so we can factor it
out. This leaves
=![]()
Practice problem:
Solve
solution ![]()
Rationalize the numerator of
. To do this multiply
by 1 in the form
.
.
Notice that the original expression was undefined at h=0 but the last expression is defined at h=0.
Solve
Put it over a common
denominator. To do this multiply
by 1 in the form of
. This leaves
which is 0 at
Both are between -1
and 1 where the expressions are defined.