JEE Mains · Maths · STD 12 - 9. differential equations
If \(\frac{d x}{d y}=\frac{1+x-y^2}{y}, x(1)=1\), then \(5 x(2)\) is equal to :
- A \(5\)
- B \(8\)
- C \(7\)
- D \(7\)
Answer & Solution
Correct Answer
(A) \(5\)
Step-by-step Solution
Detailed explanation
\( \frac{d x}{d y}-\frac{x}{y}=\frac{1-y^2}{y} \) \( \text { Integrating factor }=e^{\int-\frac{1}{y} d y}=\frac{1}{y} \) \( x \cdot \frac{1}{y}=\int \frac{1-y^2}{y^2} d y \) \( \frac{x}{y}=\frac{-1}{y}-y+c \) \( x=-1-y^2+c y \) \( x(1)=1 \) \( 1=-1-1+c \Rightarrow c=3\)…
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