WBJEE · Maths · Application of Derivatives
The equation of normal of \(x^2+y^2-2 x+4 y-5=0\) at \((2,1)\) is
- A \(y=3 x-5\)
- B \(2 y=3 x-4\)
- C \(y=3 x+4\)
- D \(y=x+1\)
Answer & Solution
Correct Answer
(A) \(y=3 x-5\)
Step-by-step Solution
Detailed explanation
Hints: \(0(1,-2) \mathrm{A}(2,1)\) Slope \(A \rightarrow \frac{y-1}{-2-1}=\frac{x-2}{1-2}, \quad \frac{y-1}{-3}=\frac{x-2}{-1}=1, y-1=3(x-2)\) \(y=3 x-5\)
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