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प्रश्न
If two zeroes of the polynomial x3 + x2 − 9x − 9 are 3 and −3, then its third zero is
पर्याय
-1
1
-9
9
उत्तर
Let `alpha = 3` and `beta = -3` be the given zeros and y be the third zero of the polynomial `x^3 + x^2 -9x-9` then
Bt using `alpha + beta + y = (-text{coefficient of }x^2)/(text{coefficient of } x^3)`
`alpha + beta + y = -1/1`
`alpha + beta + y = -1`
Substituting `alpha = 3` and `beta =-3` in `alpha + beta + y = -1`, we get
` 3 - 3 + y =-1`
`y = -1`
Hence, the correct choice is `(a).`
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