Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Differential Equations

Question:

The general solution of the differential equation $\frac{dy}{dx}=1+x+ y +xy $ is given by :

Options:

$log(1+y)=x+\frac{x^2}{2}+C,$ where C is a constant

$log\, y =x+\frac{x^2}{2}+C,$ where C is a constant

$log (y-1)=x+\frac{x^2}{2}+C,$ where C is a constant

$log (1+y)=x-\frac{x^2}{2}+C,$ where C is a constant

Correct Answer:

$log(1+y)=x+\frac{x^2}{2}+C,$ where C is a constant

Explanation:

The correct answer is Option (1) → $log(1+y)=x+\frac{x^2}{2}+C,$ where C is a constant

$\frac{dy}{dx}=1+x+ y +xy=(1+x)+y(1+x)$

$\frac{dy}{dx}=(1+x)+(1+x)$

so $\int\frac{1}{1+y}dy=\int (1+x)dx$

$⇒\log(1+y)=x+\frac{x^2}{2}+C$