[tex]4x^2-x=0\\x(4x-1)=0\\x=0\\4x-1=0\\4x=1\\x=\dfrac 14[/tex]

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[tex]25x^2=0\\x^2=0\\x=0[/tex]

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[tex]50x^2-2=0\\50x^2=2\\25x^2=1\\x^2=\dfrac{1}{25}\\x= \pm \dfrac 15[/tex]

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[tex]4x^2=64\\x^2=16\\x=\pm 4[/tex]

Ответ:

Неполные квадратные уравнения можно решать, не находя дискриминант .

[tex]1)\ \ 4x^2-x=0\ \ \Rightarrow \ \ \ x\, (4x-1)=0\ \ ,\\\\\boldsymbol{x_1=0}\ \ ,\ \ \ \boldsymbol{x_2=\dfrac{1}{4}=0,25}\\\\\\2)\ \ 25x^2=0\ \Big|:25\ \ \ \Rightarrow \ \ \ \ x^2=0\ \ ,\\\\\boldsymbol{x=0}\\\\\\3)\ \ 50x^2-2=0\ \ \ \Rightarrow \ \ \ x^2=\dfrac{2}{50}\ \ ,\ \ \ x^2=\dfrac{1}{25}\ \ ,\\\\\boldsymbol{x_{1,2}=\pm \dfrac{1}{5}=\pm 0,2}\\\\\\4)\ \ 4x^2=64\ \Big|:4\ \ \ \Rightarrow \ \ \ \ x^2=16\\\\\boldsymbol{x_{1,2}=\pm 4}[/tex]