Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Differential Equations

Question:

Solution of the differential equation $(x+2y^3)\frac{dy}{dx}=y$ is:

Options:

$x=y^2(c+y^2)$

$x=y(c-y^2)$

$x=2y(c-y^2)$

$x=y(c+y^2)$

Correct Answer:

$x=y(c+y^2)$

Explanation:

$(x+2y^3)\frac{dy}{dx}=y⇒\frac{dx}{dy}=\frac{x}{y}+2y^2$ [Bernoull’s Differential equation]

$⇒\frac{dx}{dy}-\frac{x}{y}=2y^2$ where $I.F.=e^{\int-\frac{1}{y}dy}=\frac{1}{y};x.\frac{1}{y}=\int\frac{2y^2}{y}dy+c⇒\frac{x}{y}=y^2+c$