Coordinate transformation of B & jacobian

[vernal hemlock]

Hello I was doing this question and got stuck on part b of it.
I tried doing B(x,y)=(u,r) and letting B= (a,b,c,d) (2x2) and solving (x,y)=B^-1 x (u,r), but got nowhere and later realised that I dont think i should be doing the inverse yet cus part c asks for it.
I am a little lost on what to do now.

[unique chasm]

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Once you've got your answer and you're all set, you can close this thread by typing +close, and then you can click the Thank buttons to show your Helper some appreciation. · Apr 15, 2026, 4:10 PM

[vernal hemlock]

i was doing this but tbh this seems so useless to do since we are trying to find B

[dire tusk]

you're told what B is

$B(x,y)=(xy,-x^2/2+y^2/2)$ from reading the questions

[ivory dock]

Omega

[vernal hemlock]

omg i see it now

i just cant read i see

tysm

[dire tusk]

+close if you're done then

[vernal hemlock]

what is the cmd for giving credits?

[dire tusk]

.

[vernal hemlock]

+close

[unique chasm]

Please thank your Helpers before closing!

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[vernal hemlock]

i see

[unique chasm]

Thank you for your feedback! Omega has been awarded 1 :helper_points:. They now have 920 :helper_points:. They have 3 :helper_points: daily left for today.