Q85 / 150 · MHT CET 2025 (26 Apr Shift 1) · Mathematics
The equation of the tangent to the curve $\left(1+x^2\right) y=2-x$, where it crosses the X-axis, is
- Correct answerA$x+5 y=2$
- B$x-5 y=2$
- C$5 x-y=10$
- D$5 x+y-10=0$
Solution
The curve $(1 + x^2)y = 2 - x$ intersects the X-axis when $y = 0$, yielding $x = 2$ at the point of tangency $(2, 0)$.
Differentiating implicitly using the product rule: $2x \cdot y + (1 + x^2) \frac{dy}{dx} = -1$.
At $(2, 0)$, this simplifies to $5 \frac{dy}{dx} = -1$, so the slope is $m = -\frac{1}{5}$.
Using point-slope form: $y = -\frac{1}{5}(x - 2)$, which simplifies to $x + 5y = 2$.
The correct answer is: A
Hence, the correct answer is option: 'A'.