Arthur D. answered 09/11/18
Tutor
4.9
(125)
Forty Year Educator: Classroom, Summer School, Substitute, Tutor
√128=√(2*2*2*2*2*2*2)=√(27)
the square root a number is the same as the number raised to the (1/2) power; 2 is understood to be the index of the radical when no index is written, that is, square root
for example, √36=36(1/2) (which equals 6)
therefore, √(27)=(27)(1/2)
when you have a power raised to a power you multiply the exponents
therefore, (27)(1/2)=2(7/2) because 7*(1/2)=7/2
in 7/2, 2 is the index and 7 is the power of 2