化简(x^2-2x 1分之x^-1 x 1分之1-x)
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 12:57:59
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(2x-y)/(x+3y)=2所以原式=2(2x-y)/(x+3y)-3(x+4y)/(2x-y)=2(2x-y)/(x+3y)-3/[(2x-y)/(x+3y)]=2×2-3/2=5/2
原式=[(x+2)/x(x-2)-(x-1)/(x-2)²]*x/(x-1)(x-4)*(x-2)²=(x²-4-x²+x)/x(x-2)²*x/(x
x²-4x+2=0由韦达定理得:x1+x2=4,x1·x2=2∴(1)x1+x2+3x1x2=4+3*2=10(2)x2/x1+x1/x2=(x2²+x1²)/x1x2=
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
x1+x2=5;x1x2=1;(1)x1/x2+x2/x1=(x1²+x2²)/(x1x2)=((x1+x2)²-2x1x2)/(x1x2)=(25-2)/1=23;(2
(1/x-1-1/x1)/x/2x22-2=(x/x2-x-x-1/x2-x)×2x2-2/x=1/x2-x×2x2-2/x=1/x(x-1)×2(x-1)(x+1)=2(x+1)/x2=2x+2/x
利用x1+X2=-B/A,x1x2=C/A(1)1/x1+1/x2=(x1+x2)/x1x2=-(-6/2)/(3/2)=-2(2)在菱形ABCD中边长是5,所以有OA^2+OB^2=5^2=25OA
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-5分之x-5-x分之x)\x的平方-25分之2x=2x/(x-5)*(x-5)(x+5)/2x=x+5
x/4+0.75x=1/82x+0.75=12x=0.25x=0.1254(x+0.2)=1.24x=1.2-0.84x=0.4x=0.15x-1/3=2/315x-1=215x=3x=0.2可以重新
规律:解为X1=c;X2=m/c下面的方程,在等号两边同时-1,则令y=(x-1),c=(a-1);由上面的规律的的,y1=c,y2=2/c;带入x即可
x+2/x=c+2/c~x1=c,x2=2/c;x+2/(x-1)=a+2/(a-1);(x-1)+2/(x-1)=(a-1)+2/(a-1);x1-1=a-1;x2-1=2/(a-1);x1=a;x
f(x)在x=1处左右导数存在再问:左右都存在?
(1)解是x1等于a,x2等于a分之2(2)在方程x+X分之2=a+a分之2两边同时乘以ax,得出a乘以(x的平方)+2a=(a的平方)乘以x+2x,移项后得到a乘以(x的平方)-(a的平方+2)乘以
2√2-2或-2√2-2
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