Problem 11
Find the general solution of the differential equation. \(y \ln x-x y^{\prime}=0\)
Problem 11
Write and solve the differential equation that models the verbal statement. The rate of change of \(Q\) with respect to \(t\) is inversely proportional to the square of \(t\).
Problem 13
Write and solve the differential equation that models the verbal statement. The rate of change of \(N\) with respect to \(s\) is proportional to \(250-s .\)
Problem 15
Slope Fields,( a) sketch an approximate solution of the differential equation satisfying the initial condition by hand on the slope field, (b) find the particular solution that satisfies the initial condition, and (c) use a graphing utility to graph the particular solution. Compare the graph with the handdrawn graph of part (a). To print an enlarged copy of the graph, select the MathGraph button. $$ \begin{array}{ll} \underline{\text { Function }} & \underline{\text { Differential Equation }} \\\ \frac{d y}{d x}=e^{x}-y& \quad (0,1) \end{array} $$
Problem 20
Find the function \(y=f(t)\) passing through the point \((0,10)\) with the given first derivative. Use a graphing utility to graph the solution. $$ \frac{d y}{d t}=\frac{3}{4} y $$
Problem 22
Write and solve the differential equation that models the verbal statement. Evaluate the solution at the specified value of the independent variable. The rate of change of \(N\) is proportional to \(N .\) When \(t=0\), \(N=250\) and when \(t=1, N=400 .\) What is the value of \(N\) when \(t=4 ?\)
Problem 25
Solve the Bernoulli differential equation. $$ y^{\prime}+3 x^{2} y=x^{2} y^{3} $$
Problem 28
Solve the Bernoulli differential equation. $$ y^{\prime}+\left(\frac{1}{x}\right) y=x \sqrt{y} $$
Problem 30
Solve the Bernoulli differential equation. $$ y y^{\prime}-2 y^{2}=e^{x} $$
Problem 30
Give the differential equation that models exponential growth and decay.