You really should learn to type in LaTex. I can barely read your post.

You mean this?1. 12u cubed/7v to the fifth * 14v squared/3u =

8 u squared/ v cubed

If so, then

It's correct.

You mean this?2. 9x * 4/x =

36?

If so, and assuming that x isn't 0, then 36 is right.

I'm not even touching this one.3. x squared -3x +2/x squared -4x +4 divided by x squared -2x +1/ 3x squared -12 =

3(x+2)/ (x-1)

You mean this?4. 15 divided by 5x/x+1 =

3(x+1) / x

You mean this?5. 6x/x-2 divided by 3x =

2/x-2

01