P^2q=4p-3

2*p(dp/dq)*q + p^2 = 4(dp/dq)

now get dp/dq on one side:

p^2 = 4(dp/dq) - 2*p*q(dp/dx)

p^2 = (dp/dq) (4 - 2pq)

p^2 /(4 - 2pq) = dp/dq

dp/dq = p^2 /(4 - 2pq)

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