作业帮1x2/1+2x3/1+3x4/1+.+2009x2010/1=? 2x4/1+4x6/1+6x8/1+.+2010x2012/1=?很急!1!
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/15 17:01:17
1x2/1+2x3/1+3x4/1+.+2009x2010/1=? 2x4/1+4x6/1+6x8/1+.+2010x2012/1=?很急!1!
1x2/1+2x3/1+3x4/1+.+2009x2010/1=? 2x4/1+4x6/1+6x8/1+.+2010x2012/1=?
很急!1!
1x2/1+2x3/1+3x4/1+.+2009x2010/1=? 2x4/1+4x6/1+6x8/1+.+2010x2012/1=?很急!1!
1x2/1+2x3/1+3x4/1+.+2009x2010/1
=1-2/1+2/1-3/1+3/1-4/1+……+2009/0-2010/1
=1-2010/1
=2010/2009
2x4/1+4x6/1+6x8/1+.+2010x2012/1
=2/1x(2/1-4/1+4/1-5/1+5/1-8/1+……+2010/1-2012/1)
=2/1x(2/1-2012/1)
=4024/1005
切点(a,a³+2)
y'=3x²
斜率k=3a²
所以切线是y-(a³+2)=3a²(x-a)
y=kx过原点
-a³-2=-3a²
a³-3a²+2=0
(a-1)(a²-2a-2)=0
a=1,a=1±√2
k=3a²
k=3
k=9-6√2
k=9+6√2
用克拉默法则解下列方程组 x1-2x2+3x3-4x4=4 x2-x3+x4=-3 x1+3x2+2x4=1 -7x2+3x3+x4=3x1-2x2+3x3-4x4=4x2-x3+x4=-3 x1+3x2+2x4=1 -7x2+3x3+x4=3
因式分解：x4+x3+2x2 +x+1
解方程组X1-2x2+3x3-x4=1,3x1-x2+5x3-3x4=2,2x1+x2+2x3-2x4=3
x1+5x2-x3-x4=-1x1-2x2+x3+3x4=33x1+8x2-x3+x4=1
写出方程组2*x1+x2-x3+x4=1,x1+2*x2+x3-x4=2,x1+x2+2*x3+x4=3的通解?
求非齐次线方程组的通解 ：2x1+x2-x3+x4=1 x1+2x2+x3-x4=2 x1+x2+2x3+x4=3
具体写出方程组：2x1+x2-x3+x4=1;x1+2x2+x3-x4=2;x1+x2+2x3+x4=3的通解
解一道方程组x1+x2+x3=5,x2+x3+x4=1,x3+x4+x5=-5,x4+x5+x1=-3,x5+x1+x2=2
用初等行变换来解下列线性方程组（1）2x1-x2+3x3=3 3x1+x2-5x3=0 4x1-x2+x3=3 x1+3x2-13x3=-6(2) x1-2x2+x3+x4=1 x1-2x2+x3-x4=-1 x1-2x2+x3-5x4=5(3) x1-x2+x3-x4=1 x1-x2-x3+x4=0 x1-x2-2x3+2x4=-1/2
1X2+2X3+3X4+.NX(N+1)
1X2+2X3+3X4+.NX(N+1)规律
1x2+2x3+3x4+.+2011x2012
1x2+2x3+3x4+4x5+.+15x16
1x2+2x3+3x4+.+100x101=
1x2+2x3+3x4+.+100x101=?结果
1x1!+2x2!+3x3!+4x4!.nxn!
1X2+2x3+3x4+……+2013x2014
1x2+2x3+3x4+.+19x20