9709 P33 - Jun 2013 - Q8
2278
The variables x and t satisfy the differential equation
\(t \frac{dx}{dt} = \frac{k - x^3}{2x^2}\),
for \(t > 0\), where \(k\) is a constant. When \(t = 1, x = 1\) and when \(t = 4, x = 2\).
(i) Solve the differential equation, finding the value of \(k\) and obtaining an expression for \(x\) in terms of \(t\). [9]
(ii) State what happens to the value of \(x\) as \(t\) becomes large. [1]
