Practicing Success
Particular solution of y1 + 3xy = x which passes through (0, 4) is : |
$3 y=1+11 e^{-\frac{3 x^2}{2}}$ $y=\frac{1}{3}+11 e^{-x^2}$ $y=1+\frac{11}{3} e^{-x^2}$ $y=\frac{1}{3}+11 e^{\frac{3}{2} x^2}$ |
$3 y=1+11 e^{-\frac{3 x^2}{2}}$ |
$\frac{d y}{d x}+(3 x) y=x $ I.F = $e^{\int 3 x d x}=e^{\frac{3}{2} x^2}$ ∴ Solution of given equation is $ye^{\frac{3}{2} x^2}=\int x . e^{\frac{3}{2} x^2} d x+c=\frac{1}{3} e^{\frac{3}{2} x^2}+c$ If curve passes through (0, 4), then $4 \frac{1}{3}=c \Rightarrow c=\frac{11}{3}$ $y=\frac{1}{3}+\frac{11}{3} e^{-\frac{3}{2} x^2} \Rightarrow 3 y=1+11 e^{-\frac{3}{2} x^2}$ Hence (1) is the correct answer. |