161

tick cho mk nha

dinh lua a nam mo nguoi ta tink

Nowadays teenagers rely more on technology than in the past.

Ta có: \(x^2-x+1\)

\(=x^2-2.x.\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{3}{4}\)

\(=\left(x^2-2.x.\dfrac{1}{2}+\dfrac{1}{4}\right)+\dfrac{3}{4}\)

\(=\left(x-\dfrac{1}{2}\right)^2+\dfrac{3}{4}\ge\dfrac{3}{4}>0\) \(\forall x\)

Vậy \(x^2-x+1>0\forall x\)

Mai / good / at/ Math/ than / Lan Anh.

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4119 nhe tick mình