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Consider the quadratic equation \(\left({n}^{2}-2n+2\right){x}^{2}-3x+{\left({n}^{2}-2n+2\right)}^{2}=0,n\in R\). Let \(…

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Consider the quadratic equation \(\left({n}^{2}-2n+2\right){x}^{2}-3x+{\left({n}^{2}-2n+2\right)}^{2}=0,n\in R\). Let \(\alpha\) be the minimum value of the product of its roots and \(\beta\) be the maximum value of the sum of its roots. Then the sum of the first six terms of the G.P., whose first term is \(\alpha\) and the common ratio is \(\frac{\alpha }{\beta }\), is:

[JEE Main 2026, 6 Apr (Shift 2)]

a

\(\frac{61}{37}\)

b

\(\frac{121}{81}\)

c

\(\frac{364}{243}\)

d

\(\frac{1093}{729}\)

✓ Correct answer: c)

\(\frac{364}{243}\)

Explanation

We have \(\left(n^2-2 n+2\right) x^2-3 x+\left(n^2-2 n+2\right)^2=0\)

Since \(n^2-2 n+2=(n-1)^2+1\)

Sum of roots \(=\frac{3}{(n-1)^2+1}\)

Since the denominator is minimum when \((n-1)^2=0\)

Therefore \(\beta=3\)

Product of roots \(=(n-1)^2+1\)

So the minimum value of the product is clearly

\(\alpha=1\)

Now, first term \(a=\alpha=1\)

Common ratio \(r=\frac{\alpha}{\beta}=\frac{1}{3}\)

Now, \(S_6=1 \cdot \frac{1-\left(\frac{1}{3}\right)^6}{1-\frac{1}{3}}\)

\(S_6=\frac{1092}{729}=\frac{364}{243}\)

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