Hi, everyone

I've just joined this forum.

Hope you can help me solve my problem which has bothered me for a long long time.

maybe I've missed sth crucial.

It's about Jacobian of changing variable

http://tutorial.math.lamar.edu/Class...es/eq0029M.gif

http://tutorial.math.lamar.edu/Class...es/eq0033M.gif

1. is it ?

2. if (1) is true, can you show me how to calculate .

Because I have calculated many times but I find that They are not the same

HELP