早教吧作业答案频道 -->数学-->
已知x^2-3x+1=0,求x^3+1/x^3
题目详情
已知x^2-3x+1=0,求x^3+1/x^3
▼优质解答
答案和解析
x^2-3x+1=0
x^2+1=3x
x+1/x=3
x^3+1/x^3=(x+1/x)(x^2-1+1/x^2)=(x+1/x)[(x+1/x)²-3]=3×(3²-1)=24
x^2+1=3x
x+1/x=3
x^3+1/x^3=(x+1/x)(x^2-1+1/x^2)=(x+1/x)[(x+1/x)²-3]=3×(3²-1)=24
看了已知x^2-3x+1=0,求x...的网友还看了以下:
数学:如果m,n满足等式x^2+mx-15=(x+3)(x+n)求m+n的值1.如果m,n满足等式 2020-05-17 …
在线等高一的指数与指数幂的运算1.已知a^x=根号2+1求(a^2x)-(a^-2x)/(a^x) 2020-05-20 …
(1)解出下列方程的解:(x^2-x)^2-5(x^2-x)+6=0(2)解出下列方程的解:(x+ 2020-05-22 …
1.若X∧2+X=-1,求2X(X+1)+3的值.2.已知2X∧2-3X+2=0,求X∧2+1/X 2020-07-19 …
1已知x,y,z为实数,且满足:x+2y-z=6,x-y+2z=3求:x^2+y^2+z^2的最小 2020-07-21 …
1.计算(x-y+4xy/(x-y))(x+y-4xy/(x+y))2.已知x/(x^2-x+1)= 2020-10-31 …
几道初二数学题1.计算(x-y+4xy/(x+y))(x+y-4xy/(x+y))2.已知x/(x^ 2020-10-31 …
1.已知y=√x-2-√2-x+5,求y/x的值2.已知√x-2y+1+√2x+y-1=0求x+y的 2020-11-01 …
几道初二数学题目!~~~~1.已知y-2与x成正比例关系,且当x=1时y=6.(1)求x与y之间的函 2020-11-07 …
请帮我做下列题目:1计算:(a+b)2(a-b)2(a2-ab+b2)(a2+ab+b2)2注:2为 2020-11-07 …