先化简,再求值:[(x-y)2+(x+y)(x-y)]÷2x,其中x=2005,y=2004.
题型:解答题难度:一般来源:不详
先化简,再求值:[(x-y)2+(x+y)(x-y)]÷2x,其中x=2005,y=2004. |
答案
[(x-y)2+(x+y)(x-y)]÷2x, =(x2-2xy+y2+x2-y2)÷2x, =(2x2-2xy)÷2x, =x-y, 当x=2005,y=2004时,原式=2005-2004=1. |
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