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Question
If one zero of the quadratic polynomial f(x) = 4x2 − 8kx − 9 is negative of the other, find the value of k.
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Solution
Since α and -α are the zeros of the quadratic polynomial f(x) = 4x2 − 8kx − 9
α - α = 0
`(-"coefficient of x")/("coefficient of "x^2)=0`
`(-8k)/4=0`
-8k = 0 x 4
-8k = 0
`k=0/-8`
k = 0
Hence, the value of k is 0.
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