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The solution of differential equation `(dy)/(dx)+(2xy)/(1+x^(2))=(1)/(1+x^(2))^(2)"is"`A. `y(1+x^(2))=C+tan^(-1)x`B. `(y)/(1+x^(2))=C+tan^(-1)x`C. `y log (1+x^(2))=C+tan^(-1)x`D. `(1+x^(2))=C+sin^(-1)x`

Answer» Given that, `" "(dy)/(dx)=(2xy)/(1+x^(2))=(1)/((1+x^(2))^(2))`
Here, `" "P=(2x)/(1+x^(2)) and Q = (1)/((1+x^(2))^(2))`
which is a linear differential equation.
`therefore " "IF=e^(int(2x)/(1+x^(2))dx)`
Put `" "1+x^(2)=trArr2xdx=dt`
`therefore " "IF=e^(int(dt)/(t))=e^(logt)=e^(log(1+x^(2)))=1+x^(2)`
The general solution is
`" "y*(1+x^(2))=int(1+x^(2))(1)/((1+x^(2))^(2))+C`
`rArr" "y(1+x^(2))=int(1)/(1+x^(2))dx+C`
`rArr" "y(1+x^(2))=tan^(-1)x+C`


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