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What is wrong with the proof?
Algebra
Level 3
Let
$x$
be a solution of
$x^{2} + x + 1 = 0$
Since
$x$
is not 0, we can divide both sides by
$x$
:
$x + 1 + \frac{1}{x} = 0$
Substitute
$x + 1 = -x^{2}$
$\frac{1}{x} = x^{2}$
$x = 1$
$x = x^{3}$
$3 = 0$
$1^{2} + 1 + 1 = 0$
Step 2 because
$x$
is imaginary
Nothing is wrong!
Step 1 because there are no solutions
Step 3 because it adds an extra solution
Submit
Excel in math and science
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