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If one root of the quadratic equation 2x...

If one root of the quadratic equation `2x^(2)+kx-2=0` is -2, find the value of k.

Text Solution

Verified by Experts

The correct Answer is:
The value of k is 3.
x=-2 is the root of the given quadratic equation.
`:.` substitute x=-2 in the given quadratic equation.
`:.2(-2)^(2)+k(-2)-2=0`
`:.2(4)-2k-2=0`
`:.8-2k-2=0`
`:.-2k=2-8:.-2k=-6:.k=(-6)/(-2):.k=3`
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Knowledge Check

  • If the roots of the quadratic equation 2x^(2)+8x+k=0 are equal, find the value of k .

    A
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    B
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