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Differential Equations

Given that a lake is affected by an algae bloom covering 1.5 square meters on October 3rd, and grows at a rate proportional to the quantity present covering 4 square meters on October 15th, use a differential equation to find an expression for the area covered at time T. How long will it take to completely cover a lake surface of 5 square kilometers if growth continues in this fashion?

Using the Wronskian method, determine if the functions y1=2t1y_1 = 2t - 1, y2=t2+5y_2 = t^2 + 5, and y3=4t7y_3 = 4t - 7 are linearly independent.

For two functions y1=e2xy_1 = e^{2x} and y2=e2xy_2 = e^{-2x}, determine if they are linearly independent using the Wronskian test.

Using the Wronskian test, determine if the functions y1=cos(x)y_1 = \, \cos(x) and y2=sin(x)y_2 = \, \sin(x) are linearly independent.

Using the Improved Euler's method, solve for the approximate value of yy at x=1.3x = 1.3 for the differential equation y=xyy' = x \cdot y with the initial condition y(1)=1y(1) = 1 and a step size h=0.1h = 0.1.

Using the Euler and improved Euler techniques, approximate the values of yy given the initial conditions and a step size.

Given dydx=f(x,y)\frac{dy}{dx} = f(x, y) with x0=3,y0=2x_0 = 3, y_0 = 2, step size h=0.1h = 0.1, approximate yy when x=3.1x = 3.1 using the Euler method.

Using Euler's method with step size h=0.1h = 0.1, approximate yy when x=1.1x = 1.1 given that x0=1,y0=1x_0 = 1, y_0 = 1 and f(x,y)=x+3+sin(y)f(x, y) = x + 3 + \sin(y).

Using the improved Euler's method, approximate yy when x=1.2x = 1.2 given that x0=1,y0=1x_0 = 1, y_0 = 1, h=0.1h = 0.1, and f(x,y)=x+3+sin(y)f(x, y) = x + 3 + \, \sin(y).

Using the improved Euler method, with initial conditions x0=0x_0 = 0 and y0=1y_0 = 1, and a step size h=0.5h = 0.5, calculate the value of yy for x=0.5x = 0.5.

Use Runge-Kutta with step size H=0.1H = 0.1 to estimate y(0.2)y(0.2) in the initial value problem y=t2+y2y' = t^2 + y^2 and y(0)=1y(0) = 1.

Compute the inverse Laplace transform of the expression 2(s+1)3\frac{2}{(s+1)^3}.

Find the inverse Laplace transform of ss22s+5\frac{s}{s^2 - 2s + 5} using the method of completing the square.

Compute the inverse Laplace transform of a rational function using partial fractions when the denominator has repeated linear factors.

Find the inverse Laplace transform of 3s+8s2+2s+5\frac{3s + 8}{s^2 + 2s + 5}

Find the inverse Laplace transform of the function f(s)=1s316s2+9f(s) = \frac{1}{s - 3} - \frac{16}{s^2 + 9}.

Dirichlet problem for the Laplace equation with the region defined as the upper half plane.

Robin's problem example: uxx+uyy=0u_{xx} + u_{yy} = 0, in polar coordinates Δ2u=0\Delta^2 u = 0 on a disk with radius 1. Boundary condition: ur\frac{\partial u}{\partial r} at r=1r = 1 plus hh into Function f(x)f(x).