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Question
Find if x = – 1 is a root of the equation 2x² – 3x + 1 = 0.
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Solution
2x² – 3x + 1 = 0; x = -1.
Putting x = -1 in L.H.S. of equation
L.H.S. = 2(-1)2 - 3 x -1 + 1
= 2 + 3 + 1
= 6 ≠ 0 ≠ R.H.S.
Hence, x = -1 is not a root of the equation.
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