WBJEE · Maths · Parabola
If the parabola \(x^{2}=a y\) makes an intercept of length \(\sqrt{40}\) units on the line \(y-2 x=1\), then \(a\) is equal to
- A 1
- B -2
- C -1
- D 2
Answer & Solution
Correct Answer
(B) -2
Step-by-step Solution
Detailed explanation
Gven, equation of the parabola \(x^{2}=a y\) ie \(y=\frac{x^{2}}{a}\) and the equation of line \(y-2 x=1\) \(y=2 x+1\) \(\frac{x^{2}}{a}=2 x+1\) \(x^{2}=2 a x+a\) \(x^{2}-2 a x-a=0\)…
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