x^3-1=0

尉蕊砌4329已知x^2+x+1=0,求x^3+2x^2+2006的值
狐郭隶19485477163 ______ x^2=-x+2 x^3=x^2*x=-x^2+2x=-(-x+2)+2x=3x-2 x^3+2x^2+2006 =3x-2+2(-x+2)+2006 =x+2008 x^2+x-2=0 (x-1)(x+2)=0 x=1,x=-2 所以x^3+2x^2+2006=x+2008=2008或2006

尉蕊砌4329x^2 - x - 1=0求x^3 - 1/x^3的值,要过程 -
狐郭隶19485477163 ______ 解:x²-x-1=0 x-1-1/x=0 x-1/x=1(x-1/x)²=1² x²+1/x²-2=1 x²+1/x²=3 于是 x³-1/x³=(x-1/x)(x²+1/x²+1)=1*(3+1)=4 图片格式

尉蕊砌43292x^2 - x^3 - 1=0 的解... -
狐郭隶19485477163 ______ 2x^2-x^3-1=0 x^2-1+x^2-x^3=0 (x-1)(x+1)+x^2(1-x)=0 (x-1)(x+1)-x^2(x-1)=0 (x-1)(x+1-x^2)=0 零加零型 x-1=0或x+1-x^2=0 接下来会算了吧 记得给我好评啊

尉蕊砌4329X^3 - 3X - 2=0怎么算?求过程(有三次方的方程有什么公式? -
狐郭隶19485477163 ______ 你好,很高兴回答你的问题 x^3-3x-2=0 x^3-1-3x+3=0 (x-1)(x^2+x+1)-3(x-1)=0 (x-1)(x^2+x-2)=0 (x-1)^2*(x+2)=0 x1=1,x2=-2

尉蕊砌4329已知x^2+2x - 1=0,求x^3 - 5x+3的值? -
狐郭隶19485477163 ______ x^2+2x-1=0 x^2=1-2x x^3-5x+3 =x*x^2-5x+3 =x(1-2x)-5x+3 =x-2(1-2x)-5x+3 =x-2+4x-5x+3 =3-2 =1

尉蕊砌4329数学题 已知X^2 - 5X - 1999=0,求代数式(X - 2)^3 - (X - 1)^2+1/(X - 2) -
狐郭隶19485477163 ______ 因为X^2-5X-1999=0,即X^2-5X=1999 所以 [(X-2)^3-(X-1)^2+1]/(X-2)=(x-2)^2-(x^2-2x+1)/(x-2)+1/(x-2) =(x-2)^2-(x^2-2x)/(x-2)-1/(x-2)+1/(x-2) =x^2-4x+4-x-1/(x-2)+1/(x-2) =x^2-5x+4 =1999+4 =2003

尉蕊砌4329已知x^2 - 16x - 1=0,求x^3 - 1/x^3的值 -
狐郭隶19485477163 ______ x^2-16x-1=0 x^2-x=16x 两边除x x-1/x=16 平方 x^2-2+1/x^2=256 x^2+1/x^2=258(x^2+1/x^2)(x-1/x)=x^3-x+1/x-x^3=258*16=4128 x^3-1/x^3=4128+x-1/x=4128+16=4144

尉蕊砌4329用极限证明方程x^5 - 3x^3 - 1=0至少有一个介于1与2之间的实根 -
狐郭隶19485477163 ______ ∵当x=1时,x^5-3x^3-1=-3当x=2时,x^5-3x^3-1=7>0.∴x^5-3x^3-1=0至少有一个介于1与2之间的实根.

尉蕊砌4329已知x^2+x - 1=0 求x^3 - 2x+2012的值 -
狐郭隶19485477163 ______ 解:∵x²+x-1=0 ∴x²=1-x ∴x³-2x=x(x²-2)=x(1-x-2)=-x²-x=-(x²+x)=-1 ∴x³-2x+2012=-1+2012=2011 祝学习进步,望采纳.不懂得欢迎追问...

尉蕊砌4329已知x^2 - 2x - 1=0,求x^3 - 2x - 1/x^3+2/x的值?已知x^2 - 2x - 1=0,求x^3 - 2x - 1/x^3+2/x的值已知x^2+y^2=z^2,xy=1,求(x+y+z)(x - y+z)( - x+y+z)(x+y - z)的值 -
狐郭隶19485477163 ______[答案] x^2-1=2x x-1/x=2 两边平方 x^2-2+1/x^2=4 x^2+1/x^2=6 x^3-2x-1/x^3+2/x =(x^3-1/x^3)-2(x-1/x) =(x-1/x)(x^2+1+1/x^2)-2(x-1/x) =2*(6+1)-2*2 =10 x^2+y^2=z^2 2xy=2 相加 x^2+2xy+y^2=z^2+2 (x+y)^2-z^2=2 (x+y+z)(x+y-z)=2 x^2+y^2=z^2 2xy=2 相减 x^2-2xy+y^...