Let y(x) be the solution of the differential equation (x3 - 2y2) dx + ...
we lave (x3 - 2y2) dx + 2xy dy = 0 ....(1) compare it with M dx + N dy = 0, we have
Mult, given eqn (1) by its I.F. we have
given y(1) = 1 ⇒c = 2
⇒ x3 + y2 = 2x2
⇒y3 = 2x2 = x3 = x3 (2 - x)
⇒ y(x) exist for all x < - 2.
⇒y(x) exist in the neighbourhood of 0.
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Let y(x) be the solution of the differential equation (x3 - 2y2) dx + ...
To solve the differential equation, we can rearrange it as follows:
(x^3 - 2y^2)dx + 2xydy = 0
Dividing by x, we get:
(x^2 - 2y^2/x)dx + 2ydy = 0
Now, let's check the exactness of the equation by verifying if it satisfies the condition:
∂(M)/∂(y) = ∂(N)/∂(x)
where M = (x^2 - 2y^2/x) and N = 2y.
∂(M)/∂(y) = -4y/x
∂(N)/∂(x) = 0
Since ∂(M)/∂(y) ≠ ∂(N)/∂(x), the equation is not exact.
To make it exact, we can multiply through by x:
x(x^2 - 2y^2/x)dx + 2xydy = 0
x^3dx - 2y^2dx + 2xydy = 0
Now, let's check the exactness of this equation:
∂(M)/∂(y) = -4y
∂(N)/∂(x) = 0
Since ∂(M)/∂(y) = ∂(N)/∂(x), the equation is exact.
Now, we need to find the integrating factor to solve the equation. The integrating factor (IF) can be found using the formula:
IF = e^(∫(∂(M)/∂(y) - ∂(N)/∂(x))/N) dx
IF = e^(∫(-4y/2xy) dx)
IF = e^(-∫(2y/2xy) dx)
IF = e^(-∫(1/x) dx)
IF = e^(-ln|x|)
IF = 1/x
Multiplying the entire equation by the integrating factor, we have:
x^2dx - 2y^2dx + 2xydy = 0
Dividing by x, we get:
xdx - 2y^2dx/x + 2ydy = 0
Integrating both sides, we have:
(1/2)x^2 - 2y^2ln|x| + y^2 = C
Using the initial condition y(1) = 1, we can substitute the values and solve for C:
(1/2)(1)^2 - 2(1)^2ln|1| + (1)^2 = C
1/2 - 2ln(1) + 1 = C
1/2 - 2(0) + 1 = C
1/2 + 1 = C
C = 3/2
Therefore, the solution to the differential equation with the initial condition y(1) = 1 is:
(1/2)x^2 - 2y^2ln|x| + y^2 = 3/2
Now, let's analyze the given options:
a) y(x) exists in the neighborhood of 2.
We cannot determine if y(x) exists in the neighborhood of 2 based on the information given.