Question

please explain it........

Answer 1

By taking LCM

2|128
2|64
2|32
2|16
2|8
2|4
2|4

Then 2² *2²*2²*2=LCM

√{2²*2²*2²*2}=√128

2*2*2√2=√128

8√2 is your answer

Answer 2

by taking 128 as product of primes we get (2×2×2×2×2×2)×2 =64 ×2
i.e. root of 128 is 8 root 2