How do you simplify #(8^ { 1/ 3} x ^ { 2/ 5} ) ^ { 1/ 2}#?

2 Answers
Dec 29, 2016

#8^(1/6)x^(1/5)#

#8^(1/6) =root(6)(8)~~1.4142134....#

Note that 1.4142134 is not as precise an answer as #8^(1/6)#

Explanation:

There are two ways of writing square root.
Suppose we wished to square root the value of #a#
Note that #a# is the same thing as #a^1#

Then we could write it as: #sqrt(a^1)#
Or we could write it as:#" "a^(1xx1/2) = a^(1/2)#
They both mean the same thing.

Suppose you has #sqrt(a^3)#
This is the same thing as #a^(3xx1/2) = a^(2/3)#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You are taking the squire root of everything inside the brackets.

#(8^(1/3)x^(2/5))^(1/2)" "->" "8^(1/3xx1/2)xxx^(2/5xx1/2)#
#" "=8^(1/6)x^(2/10)#

#" "=8^(1/6)x^(1/5)#

Dec 29, 2016

#8^(1/6)x^(1/5) =root6(8) root5(x)#

While this can be calculated, the answer is an irrational number.

Explanation:

Use the power law of indices to remove the bracket.

#(x^m)^n = x^(mxxn)#

#=8^(1/3xx1/2)x^(2/5xx1/2)#

#=8^(1/6)x^(1/5)#

This can also be written as #root6(8) root5(x)#