x-1分之1 x 1分之1 x的平方 1分之2x
来源:学生作业帮助网 编辑:作业帮 时间:2024/04/29 14:12:55
x+2分之1+x分之1=x的平方+2x分之321/(x+2)+1/x=32/(x²+2x)去分母x+x+2=32x=15检验:左边=1/17+1/15=32/255右边=32/(225+30
1/x+2/(x-1)=2/(x^2-x)1/x+2/(x-1)-2/(x^2-x)=0(x-1)/x(x-1)+2x/x(x-1)-2/x(x-1)=0[(x-1)+2x-2]/x(x-1)=0(3
是求X的值吗?不晓得对不对哈,姑且一看吧 由已知可得:
5x²+x-5=0两根x1,x2,由韦达定理得x1+x2=-1/5x1x2=-5/5=-1x1²+x2²=(x1+x2)²-2x1x2=(-1/5)²
X1+X2=-B/A=2X1*X2=C/A=1/2求得X1=1+根号2或者X1=1-根号2从而求出X2的值X1/X2+X2/X1=(X1*X1+X2*X2)/(X1X2)=6
=2x/x²-(2x-1)/x²=(2x-2x+1)/x²=1/x²
1-x+4分之x的平方=1/4(x^2-4x+4)=1/4(x-2)^2再问:1.a的平方+9b平方+6ab=2.(a-2b)的2方+8ab3.(x-y)的平方-4(x-y-1)再答:.a的平方+9b
再答:还是再答:
设x1,x2是方程2x平方+4x-3=0的两个根,则x1+x2=-2x1·x2=-3/2∴x1平方+x2平方=(x1+x2)²-2x1·x2=(-2)²-2×(-3/2)=4+3=
3x的平方+6x-1=0,韦达定理得:X1+X2=-b/a=-2,X1X2=c/a=-1/31/X1+1/X2=(X1+X2)/X1X2=-2/(-1/3)=63x的平方+6x-1=0
2x平方-5x-1=0X平方-5/2X-1/2=0X平方-5/2X=1/2X平方-5/2X+5/4的平方=1/2+5/4的平方(X-5/4)平方=33/16X-5/4=正负根号33/4X=正负根号33
=x/(x+2)(x-2)-(x-2)/(x+2)(x-2)=[x-(x-2)]/(x+2)(x-2)=2/(x²-4)
7/x(x+1)-6/(x+1)(x-1)=-1/x(x-1)两边乘以x(x+1)(x-1)得7(x-1)-6x=-(x+1)7x-7-6x=-x-12x=6∴x=3经检验:x=3是方程的解
两边乘以x(x-1)得3(x-1)+6x=73x-3+6x=79x=10x=10/9经检验:x=10/9是方程的解
x1+x2=-3/2x1x2=-21/x1+1/x2=(x1+x2)/x1x2=(-3/2)/(-2)=3/4x1²+x2²=(x1+x2)²-2x1x2=(-3/2)&
X1+X2=-6/2=-3X1*X2=-3/21/X1+1/X2=(X1+X2)/(X1X2)=-3/(-3/2)=2
x1+x2=4x1x2=-1(x1+x2)^2/(1/x1+1/x2)=(x1+x2)^2*x1x2/(x1+x2)=x1x2*(x1+x2)=-4
原式=[2x(x+1)/(x+1)(x-1)-x(x-1)/(x-1)²]÷x/(x+1)=[2x/(x-1)-x/(x-1)]×(x+1)/x=x/(x-1)×(x+1)/x=(x+1)/
2x²+5x-3=0(2X-1)(X+3)=0所以有X1=1/2X2=-3或者X1=-3X2=1/2则|x1-x2|=3.51/x1²+1/x2²=4+1/9=37/9
x的平方-1分之x除以x的平方分之x的平方=x²-(x/1)/(x²/x²)=x²-(x)/1=x²-x