MS112 Worksheet
Dr. Y. Kim
5.5 Equations Involving Radicals
Property: If
B
A
=
, then
nn
B
A
=
.
Raise both sides to a positive integral power.
This procedure sometimes results in extra solutions ( called extraneous root) which do not satisfy the
original equation. Thus, you must check each potential solution in the original equation.
Ex1)
1. Solve 223 =−x for x.
Square both sides
2. Solve 21
3 2
=−n for n.
Cube both sides
Ex2) Solve 134 −=−x for x.
Ex3)
1. 413
3
−=−x
2. 312
2
+=++ xxx
3. 242 −=− xx
Ex4) Solve
xx =+ 6
for x.
Ex5)
1. 792 =+++ xx
2. 114 =−−+ xx
3. 12819 −=+−+ xx
Change in Homework Set5.5 : 1,3,7,9,15,17,19,21,33,37,45,49, 51