(急速 现1小时内)用适当的方法解下列一元二次方程 (1)25x^-144=0 (2)3x(1-x)=2x-2 (3)x^2+3x+2=0(4)根号2x^2+3x-2根号2=0 (5)(根号2-1)x-2x^2=0(6)(根号3+根号2)x^2+2根号3x+(根号3-根号2)=0(7

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(急速 现1小时内)用适当的方法解下列一元二次方程 (1)25x^-144=0 (2)3x(1-x)=2x-2 (3)x^2+3x+2=0(4)根号2x^2+3x-2根号2=0 (5)(根号2-1)x-2x^2=0(6)(根号3+根号2)x^2+2根号3x+(根号3-根号2)=0(7
(急速 现1小时内)用适当的方法解下列一元二次方程 (1)25x^-144=0 (2)3x(1-x)=2x-2 (3)x^2+3x+2=0
(4)根号2x^2+3x-2根号2=0 (5)(根号2-1)x-2x^2=0
(6)(根号3+根号2)x^2+2根号3x+(根号3-根号2)=0
(7)(2m+1)^2+3(2m+1)+2=0

(急速 现1小时内)用适当的方法解下列一元二次方程 (1)25x^-144=0 (2)3x(1-x)=2x-2 (3)x^2+3x+2=0(4)根号2x^2+3x-2根号2=0 (5)(根号2-1)x-2x^2=0(6)(根号3+根号2)x^2+2根号3x+(根号3-根号2)=0(7
(1)25x^2-144=0
(5x-12)(5x+12)=0
x=12/5或x=-12/5
(2)3x(1-x)=2x-2
3x(1-x)+2-2x=0
3x(1-x)+2(1-x)=0
(3x+2)(1-x)=0
x=-2/3或x=1
(3)x^2+3x+2=0
(x+2)(x+1)=0
x=-2或x=-1
(4)√2x^2+3x-2√2=0
(√2x-1)(x+2√2)=0
x=√2/2或x=-2√2
(5)(√2-1)x-2x^2=0
x[(√2-1)-2x]=0
x[2x*-(√2-1)]=0
x=0或x=(√2-1)/2
(6)(√3+√2)x^2+2√3x+(√3-√2)=0
[(√3+√2)x+(√3-√2)](x+1)=0
x=(√3-√2)/(√3+√2)或x=-1
x=(√3-√2)^2/(√3+√2)(√3+√2)或x=-1
x=5-2√6或x=-1
(7)(2m+1)^2+3(2m+1)+2=0
(2m+1+1)(2m+1+2)=0
(2m+2)(2m+3)=0
2(m+1)(2m+3)=0
(m+1)(2m+3)=0
m=-1或m=-3/2