x=2 y=4,求1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+...+1/(x+2010)(y+201
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/08/26 05:55:33
x=2 y=4,求1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+...+1/(x+2010)(y+2010)的值怎么算出
x=2 y=4,求1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+...+1/(x+2010)(y+2010)
原式= 1/(2*4) + 1/(4*6) + ... + 1/(2012*2014)
= (1/2)(1/2-1/4+1/4-1/6+...+1/2012-1/2014)
= (1/2)(1/2 - 1/2014) (中间全都约掉了)
= 503/2014
原式= 1/(2*4) + 1/(4*6) + ... + 1/(2012*2014)
= (1/2)(1/2-1/4+1/4-1/6+...+1/2012-1/2014)
= (1/2)(1/2 - 1/2014) (中间全都约掉了)
= 503/2014
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)的值
已知x-y=3,xy=1,求(-2x+2x+3y)-(3xy+2y-2x)-(x+4y+xy)
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
x-y=1,xy=2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
.已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知4x=9y求(1)x+y/y (2)y-x/2x
先化简,再求值(x-y/x+y)^2÷(y-x/x^2+2xy+y^2)^2*1/x+y,其中x=-4,y=1
x=2 y=4,求1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+...+1/(x+2010)(y+201
已知1/x-1/y=4,求2x+xy-2y/x-2xy-y的值
已知1/x-1/y=4,求(2x+xy-2y)/(x-2xy-y)
已知x^2+y^2+x^2y^2-4xy+1=0 求(x-y)^2008-(xy)^2008