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Solve dy/dx = xy, y(0) = 2. Find the interval, on which the solution is defined.

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Answer:

The interval on which the solution is defined depends on the domain of the exponential function. Since e^((1/2)x^2 + ln(2)) is defined for all real numbers, the solution is defined on the interval (-∞, +∞), meaning the solution is valid for all x values.

Explanation:

o solve the differential equation dy/dx = xy with the initial condition y(0) = 2, we can separate the variables and integrate both sides.

Starting with the given differential equation:

dy/dx = xy

We can rearrange the equation to isolate the variables:

dy/y = x dx

Now, let's integrate both sides with respect to their respective variables:

∫(dy/y) = ∫x dx

Integrating the left side gives us:

ln|y| = (1/2)x^2 + C1

Where C1 is the constant of integration.

Now, we can exponentiate both sides to eliminate the natural logarithm:

|y| = e^((1/2)x^2 + C1)

Since y can take positive or negative values, we can remove the absolute value sign:

y = ± e^((1/2)x^2 + C1)

Next, we consider the initial condition y(0) = 2. Substituting x = 0 and y = 2 into the solution equation, we get:

2 = ± e^(C1)

Here, we see that e^(C1) is positive since it represents the exponential of a real number. So, the ± sign can be removed, and we have:

2 = e^(C1)

Taking the natural logarithm of both sides:

ln(2) = C1

Now, we can rewrite the general solution with the determined constant:

y = ± e^((1/2)x^2 + ln(2))

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