How do you simplify #\root[ 9] { 27a ^ { 3} b ^ { 6} } #?

1 Answer
Dec 6, 2017

#color(blue)(3^(1/3) * a ^(1/3) * b ^ (2/3))#

Explanation:

We are given the expression with radical sign.

#color(blue)(root(9)(27a^3b^6))# #..color(red)(Expression.1)#

We will be using the following formulas to simplify:

#color(green)(root(n)(a) = a^(1/n))# #..color(blue)(.. 1)#

#color(green)((a^m)^n = a^(mn))# #..color(blue)(.. 2)#

#color(green)((a^m)^(1/n) = a^(m/n))# #..color(blue)(.. 3)#

#color(green)((a*b*c)^m = a^m * b^m * c^m# #..color(blue)(.. 4)#

We write the #..color(red)(Expression.1)# as follows:

#color(blue)((27a^3b^6)^(1/9))# ..... using formula #..color(blue)(.. 1)#

In the next step, we will isolate each factor inside the parenthesis with the exponent as follows:

#color(blue)((27)^(1/9)* (a^3)^(1/9)* (b^6)^(1/9)# ..... using formula #..color(blue)(.. 4)#

We can now rewrite the above expression as follows:

#color(blue)((3^3)^(1/9)* (a^3)^(1/9)* (b^6)^(1/9)#

#color(blue)(rArr 3^(3/9) * a^(3/9)*b^(6/9))# ..... using formula #..color(blue)(.. 3)#

After simplification, we can write the above expression as:

#color(blue)(rArr 3^(1/3) * a^(1/3)*b^(2/3))#