Question 705021

We have $dx/dt = ax$ and $dp/dt = -p$.

Dividing the two equations: $dx/dp = (ax)/(-p) \implies dx/x = -a(dp/p)$.

Integrating both sides: $\ln x = -a \ln p + C$.

This implies $x = k p^{-a}$.

Since $-1 < a < 0$, let $a = -0.5$, then $x = k p^{0.5}$, which is a parabolic shape characteristic of option 1.