# Find the mistake in these mathematical equations

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Find the mistake in these mathematical equations.
x = 2
x(x-1) = 2(x-1)
x2-x = 2x-2
x2-2x = x-2
x(x-2) = x-2
x = 1

posted Jul 10, 2014
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Find the value of all these with the help of the equations below.
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+1 vote

The following is my attempt at proving that 1<-1 . In which of these steps did I first make a mistake?
Step 1: Let i = sqrt(-1) then i^2 = -1 and i^4=1.
Step 2: Hence, we have i^2 < i^4
Step 3: We divide both sides by i to get i < i^3.
Step 4: We divide both sides by i again to get 1<i^2 or 1 < -1