Q112 / 160 · AP EAMCET 2020 (21 Sep Shift 2) · Mathematics
Find \(\frac{d y}{d x}\) if \(2 x^2-3 x y+y^2+x+2 y-8=0\)
- Correct answerA\(\frac{3 y-4 x-1}{2 y-3 x+2}\)
- B\(\frac{3 y+4 x-1}{2 y-3 x+2}\)
- C\(\frac{3 y-4 x-1}{2 y+3 x+2}\)
- D\(\frac{3 y-4 x-1}{2 y-3 x-2}\)
Solution
Given equation \(2 x^2-3 x y+y^2+x+2 y-8=0\)
On differentiating w.r.t. \(x\), we get
\(\begin{aligned}
& 4 x-3 x \frac{d y}{d x}-3 y+2 y \frac{d y}{d x}+1+2 \frac{d y}{d x}=0 \\
\Rightarrow & \quad(3 x-2 y-2) \frac{d y}{d x}=4 x-3 y+1 \\
\Rightarrow & \frac{d y}{d x}=\frac{4 x-3 y+1}{3 x-2 y-2}=\frac{3 y-4 x-1}{2 y-3 x+2}
\end{aligned}\)
Hence, options (a) is correct.
Hence, the correct answer is option: 'A'.