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Question
In each of the following determine whether the given values are solutions of the equation or not.
x2 + x + 1 = 0; x = 1, x = -1.
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Solution
Given equation is
x2 + x + 1 = 0; x = 1, x = -1
Substitute x = 1 in L.H.S.
L.H.S. = (1)2 + (1) + 1
= 3 ≠ R.H.S. ≠ 0
Hence, x = 1 is not a solution of the given equation.
Now substitute x = -1 in L.H.S.
L.H.S. = (-1)2 + (-1) + 1
= 1 - 1 + 1
= 1 ≠ R.H.S. ≠ 0
Hence, x = -1 is not a solution of the given equation.
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