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प्रश्न
If one of the zeroes of the quadratic polynomial (k – 1)x2 + k x + 1 is –3, then the value of k is ______.
विकल्प
`4/3`
`(-4)/3`
`2/3`
`(-2)/3`
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उत्तर
If one of the zeroes of the quadratic polynomial (k – 1)x2 + k x + 1 is –3, then the value of k is `underlinebb(4/3)`.
Explanation:
According to the question,
–3 is one of the zeros of quadratic polynomial (k – 1)x2 + kx + 1
Substituting – 3 in the given polynomial,
(k – 1)(– 3)2 + k(–3) + 1 = 0
(k – 1)9 + k(–3) + 1 = 0
9k – 9 – 3k + 1 = 0
6k – 8 = 0
k = `8/6`
Therefore, k = `4/3`
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