\(a)x^3-0,25=0\\ \Leftrightarrow x^3-\dfrac{1}{4}=0\\ \Leftrightarrow x^3=\dfrac{1}{4}\\ x=\dfrac{\sqrt[3]{2}}{2}\)
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\(b)x^2-10=-25\\ \Leftrightarrow x^2-10x+25=0\\ \Leftrightarrow\left(x-5\right)^2=0\\ \Leftrightarrow x-5=0\\ \Leftrightarrow x=5\)
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\(c)x^2-2x-3=0\\ \Leftrightarrow x^2+x-3x-3=0\\ \Leftrightarrow x\left(x+1\right)-3\left(x+1\right)=0\\ \Leftrightarrow\left(x+1\right)\left(x-3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+1=0\\x-3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=3\end{matrix}\right.\)
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\(d)2x^2+5x-3=0\\ \Leftrightarrow2x^2+6x-x-3=0\\ \Leftrightarrow2x\left(x+3\right)-\left(x+3\right)=0\\ \Leftrightarrow\left(x+3\right)\left(2x-1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+3=0\\2x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=\dfrac{1}{2}\end{matrix}\right.\)
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