I think there is a problem in the d/dt part
A cone 4 m high, base diameter of 6 m, water is entering at 3 m^3 per minute
when water is at a height of 3 m, what is the rate of rise?
1/3pi(r^2)h = V
1/3pi(3^2)(3) = 28.274 m^3 at level of 3 m
dh/dt = ?
f'ghi + fg'hi + fgh'i + fghi' = dv/dt
0 + 0 + 1/3pi(2r)(dh/dt) + 1/3pi(r^2)(1)
working this out gets me a rate of
but I feel there is a problem in the fghi part