先化简代数式x 2分之x的平方-1除以
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原式=(x^2-1)/x÷(x^2+x)/x^2=(x-1)(x+1)/x*x^2/x(x+1)=x-1当x=2时,原式=2-1=1
X2平方+2X-3=0X2平方+2X=33X2的平方+6X-4=3(X2平方+2X)-4=3*3-4=5
原式=(x^2-1)/(x^2+2x)*(x-1)/x=(x-1)^2(x+1)/x^2(x+2),解不等式组:x+2>1,——》x>-1,2(x-1)>-6,——》x>-2,所以,解集为:x>-1,
3x2(平方)-2x=6的值为83/2x2(平方)-x=6/2=33/2x2(平方)-x+1=4
x^2-3x+2=0(x-2)(x-1)=0x=2或x=1当x=2时x^2+1/x^2=2^2+1/2^2=4+1/4=17/4当x=1时x^2+1/x^2=1^2+1/1^2=1+1=2
(x-1)^2/(x^2-1)+x^2/(x+1)=(x-1)^2/(x+1)(x-1)+x^2/(x+1)=(x-1+x^2)/(x+1)因为已知x^2-2=0,则x^2=2代入得:原式=(x-1+
再答:望采纳,谢谢
1.12.5
(1-x+2分之3)除以x+2分之1-x的平方=(x+2-3)/(x+2)÷(x-1)²/(x+2)=(x-1)/(x-1)²=1/(x-1)
X2+Y2+8X+6Y+25=0x²+8x+16+y²+6y+9=0(x+4)²+(y+3)²=0∴x+4=0y+3=0x=-4y=-3X2+4XY+4Y2分之
再问:呵呵你写错了再问:是2分之x
x-x+3=0所以x1+x2=1,x1x2=3因此(1)(X1+2)(X2+2)=x1x2+2(x1+x2)+4=3+2x1+4=9(2)(X1-X2)=(x1+x2)-4x1x2=1-4x3=-11
根据韦达定理:x1+x2=-b/ax1*x2=c/a代入:x1+x2=-5/3x1*x2=-2/3即:x1+x2+x1*x2=(-5/3)+(-2/3)=-7/3
因为x+1/x=3所以两边平方,得:x2+2x(1/x)+1/(x2)=9x2+2+1/(x2)=9即x2+1/(x2)=7
(1+(x-1分之1))除以(x的平方-1)分之x=x-1分之x乘以x分之(x+1)(x-1)=x+1额,x的值呢?
∴X的平方=2X的平方-1分之(X-1)的平方+X+1分之X的平方=(x-1)/(x+1)(x-1)+x/(x+1)=(x+x-1)/(x+1)=(2+x-1)/(x+1)=(x+1)/(x+1)=1
(x-1)^2/(x^2-1)+x^2/(x+1)=(x-1)/(x+1)+x2/(x+1)=(x^2+x-1)/(x+1)=(x+1)/(x+1)=1
x²-2=0x²=2原式=(x-1)²/(x+1)(x-1)+x²/(x+1)=(x-1)/(x+1)+x²/(x+1)=(x²+x-1)/
方法一:∵x-1/x=5∴(x-1/x)²=5²x²+1/x²-2=25x²+1/x²=23方法二:x²+1/x²=(x
x^2+1/x^2=(x+1/x)^2-2=7