用分解因式法、适当的方法解方程用分解因式法解方程:(1)(2x-5)^2-(x-2)^2=0 (2)x^2+(√5+√3

用分解因式法、适当的方法解方程
用分解因式法解方程:
(1)(2x-5)^2-(x-2)^2=0 (2)x^2+(√5+√3)x+√15=0
(3)x^2-16x+60=0 (4)(x^2+x)(x^2+x-2)=24
(5)9/4(2x+3)^2=25/36(12x-18)^2 (6)(x-√2)=√5x(2-√2x)
(7)(x+1)(x+2)=2x+4 (8)(y+2)^2=(3y-1)^2
用适当的方法解方程:
(1)25x^2-144=0 (2)3x(1-x)=2x-2
(3)x^2+3x+2=0 (4)√2x^2+3x-2√2=0
(5)(√2-1)x-2x^2=0 (6)(√3+√2)x^2+2√3x+(√3-√2)=0
(7)(2m+1)^2+3(2m+1)+2=0
(8)x^2-4x+1=0 (9)(x-1)(x+2)=70
(10)9x^2=4(3x+1) (11)2x^2-7x+2=0
(12)(4x-1)^2-10(4x-1)-24=0
(13)x^4-x^2-6=0
(14)x^2-2√5x+2=0
(15)3x(1-x)=2x-2
qzlaw 1年前 已收到1个回答 举报

eddiejean 春芽

共回答了18个问题采纳率:72.2% 举报

(1)(2x-5)²-(x-2)²=0
[(2x-5)-(x-2)][(2x-5)+(x-2)]=0
(x-3)(3x-7)=0
x=3或x=7/3
(2)x²+(√5+√3)x+√15=0
(x+√5)(x+√3)=0
x=-√5或x=-√3
(3)x²-16x+60=0
(x-6)(x-10)=0
x=6或x=10
(4)(x²+x)(x²+x-2)=24
(x²+x)²-2(x²+x)-24=0
[(x²+x)-6][(x²+x)+4]=0
∵x²+x+4=(x+½)²+15/4>0
∴x²+x-6=0
(x-2)(x+3)=0
x=2或x=-3
(5)9/4(2x+3)²=25/36(12x-18)²
[3/2(2x+3)]²-[5/6(12x-18)]²=0
[(3x+9/2)-(10x-15)][(3x+9/2)+(10x-15)]=0
(-7x+39/2)(13x-21/2)=0
x=39/14或x=21/26
(6)(x-√2)=√5x(2-√2x)
(x-√2)+√10x(x-√2)=0
(x-√2)(1+√10x)=0
x=√2或x=-(√10)/10
(7)(x+1)(x+2)=2x+4
(x+1)(x+2)-2(x+2)=0
(x+2)(x+1-2)=0
x=-2或x=1
(8)(y+2)²=(3y-1)²
(y+2)²-(3y-1)²=0
[(y+2)-(3y-1)][(y+2)+(3y-1)]=0
(-2y+3)(4y+1)=0
y=1.5或y=-0.25
(1)25x²-144=0
(5x)²=12²
5x=±12
x=±2.4
(2)3x(1-x)=2x-2
3x(x-1)+2(x-1)=0
(3x+2)(x-1)=0
x=-2/3或x=1
(3)x²+3x+2=0
(x+1)(x+2)=0
x=-1或x=-2
(4)√2x²+3x-2√2=0
(√2x-1)(x+2√2)=0
x=√2/2或x=-2√2
(5)(√2-1)x-2x²=0
[(√2-1)-2x]x=0
x=0或x=(√2-1)/2
(6)(√3+√2)x²+2√3x+(√3-√2)=0
[(√3+√2)x+(√3-√2)](x+1)=0
x=-1或x=(√3-√2)/(√3+√2)=(√3-√2)²/(√3+√2)(√3-√2)=7-2√6
(7)(2m+1)²+3(2m+1)+2=0
[(2m+1)+2][(2m+1)+1]=0
2(2m+3)(m+1)=0
m=-1或m=-1.5
(8)x²-4x+1=0
(x-2)²=3
x-2=±√3
x=2±√3
(9)(x-1)(x+2)=70
x²+x-2=70
x²+x-72=0
(x-8)(x+9)=0
x=8或x=-9
(10)9x²=4(3x+1)
9x²-12x-4=0
(3x-2)²=8
3x-2=±2√2
x=(2±2√2)/3
(11)2x²-7x+2=0
2(x-7/4)²=33/8
x-7/4=±√33/4
x=(7±√33)/4
(12)(4x-1)²-10(4x-1)-24=0
[(4x-1)-12][(4x-1)+2]=0
(4x-13)(4x+1)=0
x=13/4或x=-0.25
(13)x^4-x²-6=0
(x²-3)(x²+2)=0
∵ x²+2>0
∴x²=3;x=±√3
(14)x²-2√5x+2=0
(x-√5)²=3
x-√5=±√3
x=√5±√3
(15)3x(1-x)=2x-2
3x(x-1)+2(x-1)=0
(3x+2)(x-1)=0
x=1或x=-1.5

1年前 追问

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qzlaw 举报

还有几道.....

举报 eddiejean

ok,刚刚一次没打下。
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