That was quick. Thanks!

I didn't know what -a^0 is. So I put in something like -22^0 in the calculator and it gives me a 1, so I thought -a^0 is 1. Your proof of -a^0 is equal -1 certainly helps.

(3a/-b) (b^2/6b) (b/-a)

= (3/6) (a/-a) (b^3/-b^2)

I'm not good in math, my head is still spinning about negative fractions. Since the mistake is in -a^0, I think the (3/6) in the second step is correct. It should not be (-3/6). It sounds silly to ask this, I'm thinking in terms of other questions, Is that right? Thanks again.