Mk chỉ làm về dạng bình phương cộng( trừ ) một số thôi ,bn lại tự đánh giá nhé !
\(C=x^2-x+1\)
\(=x^2-x+\dfrac{1}{4}+\dfrac{3}{4}\)
\(=\left(x^2-x+\dfrac{1}{4}\right)+\dfrac{3}{4}\)
\(=\left(x-\dfrac{1}{2}\right)^2+\dfrac{3}{4}\)
\(E=x^2+3x+3\)
\(=x^2+3x+\dfrac{9}{4}+\dfrac{3}{4}\)
\(=\left(x^2+3x+\dfrac{9}{4}\right)+\dfrac{3}{4}\)
\(=\left[x^2+3.x.\dfrac{3}{2}+\left(\dfrac{3}{2}\right)^2\right]+\dfrac{3}{4}\)
\(=\left(x+\dfrac{3}{2}\right)^2+\dfrac{3}{4}\)
\(G=3x^2-5x+3\)
\(=x^2+x^2+x^2-2x-2x-x+1+1+\dfrac{1}{4}+\dfrac{3}{4}\)
\(=\left(x^2-2x+1\right)+\left(x^2-2x+1\right)+\left(x^2-x+\dfrac{1}{4}\right)+\dfrac{3}{4}\)
\(=\left(x-1\right)^2+\left(x-1\right)^2+\left(x-\dfrac{1}{2}\right)^2+\dfrac{3}{4}\)
\(K=4x^2+3x+2\)
\(=4x^2+3x+\dfrac{9}{16}+\dfrac{23}{16}\)
\(=\left(4x^2+3x+\dfrac{9}{16}\right)+\dfrac{23}{16}\)
\(=\left(2x+\dfrac{3}{4}\right)^2+\dfrac{23}{16}\)
