What is (18)^1/2 -(8)^1/2 simplified?

In order to answer this we will break down the two surds into their factors. So we know that 18 is 2 multiplied by 9 and so (18)^1/2=(92)^1/2 which cane be broken down into (9)^1/2(2)^1/2 .We know that (9)^1/2=3 and so (18)^1/2=((2)^1/2)3For (8)^1/2 we have that 8=42 and so by the same method as above we have (8)^1/2=(4)^1/2*(2)^1/2=2(2)^1/2So (18)^1/2-(8)^1/2=3(2)^1/2-2(2)^1/2=(2)^1/2