Simplify 3√125a^1b^3
(By the way,in 3√, 3 is the index)
3√125a^1b^3
3√125 * 3√a^1 * 3√b^3
5 * 3√a^1 * 3√b^3
I'm stuck what to do next.
Just as √125 = 5√5, √b^3 = b√b
You went a bit astray, so we should have
3√(125a^1b^3)
= 3*5b√(5ab)
= 15b√(5ab)
The 3 does not distribute across products. The distributive property only applies to addition, as in
3(√a + √b) = 3√a + 3√b