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"Được" tặng ngay 1 câu là:Được ngồi giữa bọn hoa lá ngón

( Cô giáo trêu thằng con trai ngồi ở tổ mk,bảo là được ngồi giữa một rừng hoa thế kia thì sướng quá còn gì.Thế là nó tặng cho nguyên một câu văn hoa mĩ như thế ấy)

Once upon a time,there is a girl called Little Red Riding Hood,because of the red hood she always wears.The girl walks through the woods to give her grandmother some food.A wolf want to eat the girl but is afraid to do so in public(sometimes there are woodcutters watching).So,he suggests the girl to pick some flowers,which she does.After that,he goes to the grandmother's house.He eats the grandmother,and waits for the girl,disguised as the grandmother.When the girl arrives,he eats her too.A woodcutter,however,comes to the house and cuts the wolf open.Little Red Riding Hood and her grandmother come out unharmed.

​Tên gọi khoa học của cá voi xanh là Balaenoptera muuscolus

I'm pleased to speak to you

A = \(x^2-x+1\)

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

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

Vì \(\left(x-\dfrac{1}{2}\right)^2\ge0\forall x\)

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

\(\Rightarrow A\ge\dfrac{3}{4}\forall x\)

Vậy GTNN của A là \(\dfrac{3}{4}\) khi \(\left(x-\dfrac{1}{2}\right)^2=0\) hay x = \(\dfrac{1}{2}\)

B=\(x^2-5x-2\)

=\(x^2-5x+\dfrac{25}{4}-\dfrac{33}{4}\)

=\(\left(x-\dfrac{5}{2}\right)^2-\dfrac{33}{4}\)

Vì \(\left(x-\dfrac{5}{2}\right)^2\ge0\forall x\)

\(\Rightarrow\left(x-\dfrac{5}{2}\right)^2-\dfrac{33}{4}\ge-\dfrac{33}{4}\forall x\)

\(\Rightarrow B\ge-\dfrac{33}{4}\forall x\)

Vậy GTNN của B là \(-\dfrac{33}{4}\) khi \(\left(x-\dfrac{5}{2}\right)^2=0\) hay x=\(\dfrac{5}{2}\)

\(\left(m^3-m+1\right)^2+\left(m^2-3\right)-2\left(m^2-3\right)\left(m^3-m+1\right)\)

\(=\left(m^3-m+1+m^2-3\right)^2\)

\(=\left(m^3+m^2-m-2\right)^2\)

\(x^{n-1}\left(x+y\right)-y\left(x^{n-1}+y^{n-1}\right)\)

=\(x^n+x^{n-1}y-x^{n-1}y-y^n\)

=\(x^n-y^n\)