• Rin@lemm.ee
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    1 year ago

    not sure I’m following. there are only two solutions to this. the equation is essentially:

    x² -1 = 0
    x² = 1 
    x = ±√1
    x = ±1
    => x = 1, x = -1
    

    supposing x was √-1:

    (√-1)² -1 = 0
    -1 -1 = 0
    -2 = 0
    

    therefore we can certainly conclude that x ≠ √-1