已知y1=2x² 7x-1
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y1=y2可得:2x平方-3x+1=4x平方+4x+7移项并合并同类项得:2x平方+7x+6=0分解因式得(x=2)(2x+3)=0可得x1=-2;x2=-3/2所以可知x=-2或-3/2时,y1=y
1、由2x²+7x-1=x²+6x+2得x²+x-3=0,则x=2分之(-1正负根号13)2、由(a²+b²-3)=25,得a²+b&sup
y1=y22x²+7x-1=x²+6x+2x²+x-3=0x=(-1±√13)/2
由{y=1/2x-2{y=-x+1可得1/2x-2=-x+1即x=2则y=-1所以{y=1/2x-2{y=-x+1的解是{x=2{y=-1画图后可看出:当x>2时,y1>y2当x<2时,y1
因为y1与x成正比例,y2与x减1成正比例所以可设y1=ax,y2=b(x-1)则y=ax+b(x-1)将两个点的坐标代入有:a+b(1-1)=32a+b(2-1)=7解方程组得:a=3b=1所以y=
y1=y2-2/3x+1=x2/3x+x=15/3x=1x=3/5y1=y2-5-2/3x+1=x-52/3x+x=1+55/3x=6x=18/5
y1=x²-x+3,y2=√3(2x-1)若y1=y2则x²-x+3=√3(2x-1)移项:x²-(1+2√3)x+(√3+1)√3=0(x-√3)[x-(1+√3)]=
(1)根据题意得:-23x+1=x,去分母得:-2x+3=3x,移项合并得:5x=3,解得:x=35;(2)根据题意得:-23x+1=x-4,去分母得:-2x+3=3x-12,移项合并得:5x=15,
(1)1/3(3X-5)-6X+7=2X-5/3-6X+7=2-5X=-10/3X=-2/3(2)1/3X-10+1/3(2X)-5=3X=18(3)0.3X-1/0.02-4X-8/0.5=130X
设y1=kx,y2=m(x+2),∵y=y1+y2∴y=kx+m(x+2),把x=2,y=4和x=-1,y=7代入得:2k+4m=4−k+m=7解得:k=-4,m=3,∴y=-4x+3(x+2)即y与
y1=y22x²+7x-1=6x+22x²+x-3=0(2x+3)(x-1)=0x=1x=-2/3
2x+7x=-6x-2解得x=-2/15再问:过程!!谢谢再答:当y1=-y2时即2x+7x=-6x-2解得x=-2/15亲过程很仔细了
由y1-y2=x^2-2x-3=(x-3)(x+1),得1)当x>3orxy22)当-1
解由当x=2时,y1+y2=-1得2k1+2k2=-1即k1+k2=-1/2.①当x=3时,y1-y2=12得3k1-3k2=12即k1-k2=4.②由(1)与(2)联立解得k1=7/4,k2=-9/
当y1>y2时,2x-6>-5x+1,即7x>7,解得:x>1,因此当x>1时,y1>y2.
1.y1=y2:-x+2=3x+4=>4x=-2=>x=-1/2y1-1/2y1>y2:-x+2>3x+4=>xx=1y=1带入y=ax+7=>a=-6
y1=2x-1y2=5x+7y1=y2,2x-1=5x+7,x=-8/3y1与y2互为相反数,y1=-y2,2x-1=-(5x+7),x=-6/7y1比y2小,2x-1-8/3
若y1=y2那么a^(2x-7)=a^(4x-1)∴2x-7=4x-1解得:x=-3∴x=-3时,y1=y2若y1>y2那么a^(2x-7)>a^(4x-1)当a>1时,y=a^x为增函数∴2x-7>
(1)y1=y2则17/5x+8=7/2-2x解方程.(2)y1-y2=5则17/5x+8-(7/2-2x)解方程.