Question

СРОЧНО НУЖНО ПОМОЩЬ!!!! ДАЮ 45 БАЛЛОВ​

Answer 1

Ответ:

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Answer 2

Ответ:

$x^{2} -2x=0\\D=(-2)^2-4*1*0=4\\x_{1}=\frac{2+\sqrt{4} }{2*1}=\frac{2+2}{2}=\frac{4}{2}=2\\x_{2}= \frac{2-\sqrt{4} }{2*1}=\frac{2-2}{2}=\frac{0}{2}=0 \\x_{1}=2 \\x_{2}=0$

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$2x^{2} -5x=0\\D=(-5)^2*4*2*0=25\\x_{1}=\frac{5+\sqrt{25} }{2*2}=\frac{5+5}{4}=\frac{10}{4}= 2,5\\x_{2}= \frac{5-\sqrt{25} }{2*2}=\frac{5-5}{4}=\frac{0}{4}= 0 \\x_{1}=2,5 \\x_{2} =0$

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$x^{2} +4x=0\\D=4^2-4*1*0=16\\x_{1}=\frac{-4+\sqrt{16} }{2*1}=\frac{-4+4}{2}=\frac{0}{2}=0\\x_{2}=\frac{-4-\sqrt{16} }{2*1}= \frac{-4-4}{2}=\frac{-8}{2}=-4\\x_{1} =0\\x_{2} =-4$

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$3x^{2} +x=0\\D=1^2-4*3*0=1\\x_{1}=\frac{-1+\sqrt{1} }{2*3}=\frac{-1+1}{6}=\frac{0}{6}=0\\ x_{2}=\frac{-1-\sqrt{1} }{2*3}=\frac{-1-1}{6}=\frac{-2}{6}=\frac{-1}{3}\\x_{1} =0\\x_{2} =\frac{-1}{3}$

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$3x+6x^{2} =0\\6x^{2} +3x=0\\D=3^2-4*6*0=9\\ x_{1}=\frac{-3+\sqrt{9} }{2*6}=\frac{-3+3}{12}=\frac{0}{12}=0\\x_{2}=\frac{-3-\sqrt{9} }{2*6}=\frac{-3-3}{12}=\frac{-6}{12}=-0,5\\x_{1} =0\\x_{2} =-0,5$

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$7x^{2} -7x=0\\D=(-7)^2-4*7*0=49\\x_{1}=\frac{7+\sqrt{49} }{2*7}=\frac{7+7}{14}=\frac{14}{14}=1\\x_{2}=\frac{7-\sqrt{49} }{2*7}=\frac{7-7}{14}=\frac{0}{14}=0\\x_{1} =1\\x_{2} =0$

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$2x^{2} -x=0\\D=(-1)^2-4*2*0=1\\x_{1}=\frac{1+\sqrt{1} }{2*2}=\frac{1+1}{4}=\frac{2}{4}=\frac{1}{2}=0,5\\x_{2}=\frac{1-\sqrt{1} }{2*2}=\frac{1-1}{4}=\frac{0}{4}=0\\x_{1} =0,5\\x_{2} =0$

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$0,1x^{2} -2x=0\\D=(-2)^2-4*0,1*0=4\\x_{1}=\frac{2+\sqrt{4} }{2*0,1}=\frac{2+2}{0,2}=\frac{4}{0,2}=20\\x_{2}=\frac{2-\sqrt{4} }{2*0,1}=\frac{2-2}{0,2}=\frac{0}{0,2}=0\\x_{1} =20\\x_{2} =0$

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$\frac{1}{5}x^{2} -x=0\\0,2x^{2} -x=0\\D=(-1)^2-4*0,2 *0=1\\ x_{1}=\frac{1+\sqrt{1} }{2*0,2 }=\frac{1+1}{0,4}=\frac{2}{0,4}=5\\x_{2}=\frac{1-\sqrt{1} }{2*0,2}=\frac{1-1}{0,4}=\frac{0}{0,4}=0\\x_{1} =5\\x_{2} =0$

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$-2x^{2} +4x=0\\D=4^2-4*(-2)*0=16\\x_{1}=\frac{-4+\sqrt{16} }{2*(-2)}=\frac{-4+1}{-4}=\frac{0}{-4}=0\\x_{2}=\frac{-4-\sqrt{16} }{2*(-2)}=\frac{-4-4}{-4}=\frac{-8}{-4}=2\\x_{1} =0\\x_{2} =-2$