What is the 4th root of 80?

2 Answers
Sep 19, 2015

#root(4)(80) = 2root(4)(5)#

Explanation:

If #a, b, c > 0# then #(ab)^c = a^cb^c#

#root(4)(x) = x^(1/4)#, so #root(4)(ab) = root(4)(a)root(4)(b)#

If #a, b, c > 0# then #(a^b)^c = a^(bc)#

So: #root(4)(a^4) = (a^4)^(1/4) = a^(4*1/4) = a^1 = a#

So:

#root(4)(80) = root(4)(2^4*5) = root(4)(2^4)root(4)(5) = 2root(4)(5)#

Sep 19, 2015

#root(4)80 = 2root(4)5#

Explanation:

The expression #root(4)80# can be simplified if it is possible to factor out the fourth power of some integer from #80#.

Through prime factorization, we find that #root(4)80 = root(4)(2*2*2*2*5) = root(4)(2^4*5) = root(4)(2^4)root(4)(5) = 2root(4)5#