Differential Calculus

A 600 gallon brine tank is to be cleared by piping in pure water at 1 gal/min. , and allowing the well-stirred solution to flow out at the rate of 2 gal/min. If the tank initially contains 1500 pounds of salt, a) how much salt is left in the tank after 1 hour? b) after 9 hours and 59 min?

y=x^2+C1e^2x+C2e^3x

Thank you again

How to eliminate arbitrary constants
y=C1e^x+C2e^2x+C3e^3x

thank you :)

xdx + (sin²(y/x)(ydx-xdy)) = 0

The radial stress p at distance r for the axis of the thick cylinder subjected to internal pressure is given by p + r (dp/dr) = A − p where A is a constant. If p = p₀ at the inner wall r = r₁ and is negligible (p = 0) at the outer wall r = r₂ find an expression for p.

kindly help me with my homework. eliminate the following arbitrary constants...
y= x^2 + c1 e^3x + c2 e^3x.

Differential Equations
Find the differential equations of the following family of curves.

1. Parabolas with axis parallel to the y – axis with distance vertex to focus fixed as a.
2. Parabolas with axis parallel to the x – axis with distance vertex to focus fixed as a.
3. All ellipses with center at the origin and axes on the coordinate axes.
4. Family of cardioids.
5. Family of 3 – leaf roses.

Great website, I really like it very much.
Is there any tutorial for getting the inverse of matrix (let say matrix 6x6)?

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