The function $x^2 = y\quad$ limits two areas $A$ and $B$:
$A$ is further limited with the line $x= a$, $a\gt 0$. $A$ rotates around the $x$-axis, which gives Volume $A = Va$.
$B$ is limited with the line $y=b$, $b\gt 0$. $B$ rotates around the $y$-axis, which gives Volume $B = Vb$.
What are the relations between $a$ and $b$, when $Vb = Va$?
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I have come to the solution that:
$Vb = (\pi b^2 )/ 2$
$Va = (\pi a^5) / 5$
so the relation between them is:
$2.5b^2 = a^5$
Is that the final solution or is it more?