\(32,\\ 1,\Rightarrow x^2-6x+9+x-x^2=3\\ \Rightarrow-5x=-6\\ \Rightarrow x=\dfrac{6}{5}\\ 2,\Rightarrow4x^2-8x-4x^2-4x+3=0\\ \Rightarrow-12x=-3\Rightarrow x=\dfrac{1}{4}\\ 3,\Rightarrow4x^2-4x+1+9-4x^2=8\\ \Rightarrow-4x=-2\\ \Rightarrow x=\dfrac{1}{2}\\ 4,\Rightarrow x^3-8-x^3-x^2=-17\\ \Rightarrow-x^2=-9\Rightarrow\left[{}\begin{matrix}x=3\\x=-3\end{matrix}\right.\)
\(33,\\ 1,=\left(7x-5\right)^2=\left(7\cdot5-5\right)^2=30^2=900\\ 2,=\left(x+4\right)^3=\left(6+4\right)^3=10^3=1000\\ 3,=\left(2x+y\right)^2=\left[2\cdot\left(-6\right)+2\right]^2=\left(-10\right)^2=100\\ 4,=\left(x-2\right)^3=\left(102-2\right)^3=100^3=1000000\)
\(34,\\ 1,=\left(9x^2+6x+1\right)-2=\left(3x+1\right)^2-2\ge-2\\ Dấu"="\Leftrightarrow x=-\dfrac{1}{3}\\ 2,=\left(4x^2-4x+1\right)+2=\left(2x-1\right)^2+2\ge2\\ Dấu"="\Leftrightarrow x=\dfrac{1}{2}\\ 3,=-\left(x^2-10x+25\right)-5=-\left(x-5\right)^2-5\le-5\\ Dấu"="\Leftrightarrow x=5\\ 4,=\left(5x+1\right)^2\ge0\\ Dấu"="\Leftrightarrow x=-\dfrac{1}{5}\\ 5,=\left(x^2-x+\dfrac{1}{4}\right)+\dfrac{3}{4}=\left(x-\dfrac{1}{2}\right)^2+\dfrac{3}{4}\ge\dfrac{3}{4}\\ Dấu"="\Leftrightarrow x=\dfrac{1}{2}\\ 6,=-\left(x^2-8x+16\right)+21=-\left(x-4\right)^2+21\le21\\ Dấu"="\Leftrightarrow x=4\)
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