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Question
One of the zeroes of the polynomial 2x2 + 7x – 4 is ______.
Options
2
`1/2`
`-1/2`
`-2`
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Solution
One of the zeroes of the polynomial 2x2 + 7x – 4 is `underlinebb(-1/2)`.
Explanation:
Let p(x) = 2x2 + 7x – 4
= 2x2 + 8x – x – 4 ...[By splitting middle term]
= 2x(x + 4) – 1(x + 4)
= (2x – 1)(x + 4)
For zeroes of p(x), put p(x) = 0
⇒ (2x – 1)(x + 4) = 0
⇒ 2x – 1 = 0 and x + 4 = 0
⇒ x = `1/2` and x = – 4
Hence, one of the zeroes of the polynomial p(x) is `1/2`.
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