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Fasit-svaret er 2

[tex]$${ 3 - x \equiv \sqrt {x - 1} \cr (3 - x)^2 \equiv \left( {\sqrt {x - 1} } \right)^2 \cr 9 - 3x + x^2 \equiv x - 1 \cr x^2 - 4x + 10 \equiv 0 \cr} $$[/tex]

[glem det]

Hypernicus wrote:Fasit-svaret er 2

[tex]$${ 3 - x \equiv \sqrt {x - 1} \cr (3 - x)^2 \equiv \left( {\sqrt {x - 1} } \right)^2 \cr 9 - 3x + x^2 \equiv x - 1 \cr x^2 - 4x + 10 \equiv 0 \cr} $$[/tex]

Du har gjort en liten, men vesentlig feil.

[tex](3-x)^2=9-6x+x^2[/tex]