用配方法解方程x的平方减5x加6等于0
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/13 21:42:34
x²-2√3x=5x²-2√3x+3=5+3(x-√3)=8x-√3=±2√2x=√3-2√2,x=√3+2√2
3/4x^2+3x=1,x^2+4x=4/3,(x+2)^2=4+4/3,(x+2)^2=16/3.x+2=+-4√3/3,x=+-4√3/3-2
3x²+8x-3=0x²+8x/3-1=0x²+8x/3+16/9-16/9-1=0x²+8x/3+16/9=16/9+1(x+4/3)²=25/9x
3x^2+6x-5=03(x^2+2x+1)=8(x+1)^2=8/3x1=√(8/3)-1x2=-√(8/3)-1
x^2+4X-3=0x^2+4x=3x^2+4x+(4/2)^2=3+(4/2)^2(x+2)^2=3+4=7x+2=±√7x=-2±√7x1=-2+√7x2=-2-√7
2x^2+4x-1=0x^2+2x-1/2=0x^2+2x+1-1-1/2=0(x+1)^2=3/2x+1=±√(3/2)x=-1±√(3/2)
x²+12x+36-36-15=0x²+12x+36-51=0(x+6)²=51x+6=±√51x=√51-6或x=-√51-6
解x²+px+q=0x²+px+p²/4=p²/4-q(x+p/2)²=p²/4-q∵p²-4q≥0∴p²/4>q∴x+
再答:谢谢
用配方法解方程:2x²+x-6=02x²+x-6=2(x²+x/2)-6【第一步把二次项系数变为1】=2[(x+1/4)²-1/16]-6【第二步配一次项系数的
题目是不是写错了2x^2-5x^2=3-3x^2=3x^2=-1无解再问:再问:饿再问:是错了……再问:我算一半不会算了…再答:
x^2-6x+2=0x^2-6x+9-7=0(x-3)^2=7x-3=正负根号7x=3加减根号7
用配方法解一元二次方程:2X^2-5X-3=0.方程的两边同除以2,得(x^2-5x/2-3/2=0).移项,得(x^2-5x/2=3/2).配方,得(x-5/4)^2-25/16=3/2.∴((x-
4x^2+8x+1=0(2x)^2+4x+1+4x=0(2x+1)^2+4x=0一步步解出来就OK了.
3x的平方-5x-7=0x^2-5x/3=7/3(x-5/6)^2=7/3+25/36=109/36x-5/6=±√109/6x1=5/6+√109/6x2=5/6-√109/6.
再问:3x平方减9x加二等于零。再问:用配方法解方程x(x+8)等于十六
x^2+x-1=0x^2+x=1(x^2+x+1/4-1/4)=1(x+1/2)^2=5/4x+1/2=±(√5)/2x1=(1+√5)/2x2=(1-√5)/2
x^2+10x+1=60x^2+10x+25=84(x+5)^2=84x+5=±2√21x=5+2√21或5-2√21