A. The general solution of the differential equations $\frac{d y}{d x}=\frac{1+y^2}{1+x^2}$ is $\tan ^{-1} y=\tan ^{-1} x+c$; Where c is a constant B. The general solution of the differential equation $\frac{d y}{d x}+\sqrt{\frac{1-y^2}{1-x^2}}=0$ is $\sin ^{-1} y-\sin ^{-1} x=c$; Where c is a constant C. The general solution of the differential equation $\frac{y d x-x d y}{y}=0$ is y = cx; Where c is a constant D. The general solution of the differential equation $\frac{d y}{d x}=e^{x+y}$ is $e^x+e^y=c$; Where c is a constant E. The differential equation $\left(x^2+x y\right) d y=\left(x^2+y^2\right) d x$ is homogeneous differential equation. Choose the correct answer from the options given below: |
A, B, D only A, C, E only C, D, E only D, E only |
A, C, E only |
The correct answer is Option (2) - A, C, E only (A) $\frac{d y}{d x}=\frac{1+y^2}{1+x^2}⇒\int\frac{1}{1+y^2}dy=\int\frac{1}{1+x^2}dx$ $\tan ^{-1} y=\tan ^{-1} x+c$ → True (B) $\frac{d y}{d x}+\sqrt{\frac{1-y^2}{1-x^2}}=0⇒\int\frac{+1}{\sqrt{1-y^2}}dy=\int\frac{1}{\sqrt{1-x^2}}dx$ $⇒\sin ^{-1} y-\sin ^{-1} x=c$ → False (C) $\frac{y d x-x d y}{y}=0⇒\frac{ydx-xdy}{y^2}=0$ so $\int d(\frac{x}{y})=0$ $\frac{x}{y}=k$ so $y = cx$ → True (D) $\frac{d y}{d x}=e^xe^y$ so $\int e^{-y}dy=\int e^xdx$ $-e^{-y}=e^x+c$ → False (E) $\left(x^2+x y\right) d y=\left(x^2+y^2\right) d x$ $\frac{dy}{dx}=\frac{x^2+y^2}{x^2+xy}$ $\frac{dy}{dx}=\frac{1+(\frac{y}{x})^2}{1+(\frac{y}{x})}=f(\frac{y}{x})$ → True |