已知四个数1,x,y,81/8满足条件:任意相邻的两个数中后一个数与前一个数的比都是同一个常数,求x,y的值
\u5df2\u77e5\u56db\u4e2a\u65701,x,y,81/8\u6ee1\u8db3\u6761\u4ef6:\u4efb\u610f\u76f8\u90bb\u7684\u4e24\u4e2a\u6570\u4e2d\u540e\u4e00\u4e2a\u6570\u4e0e\u524d\u4e00\u4e2a\u6570\u7684\u6bd4\u90fd\u662f\u540c\u6839\u636e\u6761\u4ef6\u5f97\u5230x/1=y/x=\uff0881/8\uff09/y
\u80fd\u89e3\u51fay=9/4.x=3/2
\u5199\u51fa\u8fd9\u6570\u5217\u7684\u524d\u51e0\u9879\uff1a
1\uff0c9\uff0c8\uff0c7\uff0c5\uff0c9\uff0c9\uff0c0\uff0c3\uff0c1\uff0c3\uff0c7\uff0c4\uff0c\u2026
\u628a\u8fd9\u4e32\u6570\u6309\u5947\u3001\u5076\u6570\u6765\u5206\u7c7b\uff0c\u53ef\u5f97\u4e0b\u9762\u6570\u4e32\uff1a
\u5947\uff0c\u5947\uff0c\u5076\uff0c\u5947\uff0c\u5947\uff0c\u5947\uff0c\u5947\uff0c\u5076\uff0c\u5947\uff0c\u5947\uff0c\u5947\uff0c\u5947\uff0c\u5076\uff0c\u2026
\u663e\u7136\u4ece\u7b2c\u56db\u4e2a\u6570\u5f00\u59cb\uff0c\u603b\u662f \u5947\uff0c\u5947\uff0c\u5947\uff0c\u5947\uff0c\u5076\u7684\u60c5\u51b5\u3002
\u56e0\u6b64\u4e4b\u540e\u7684\u6570\u4e32\u4e2d\u7edd\u4e0d\u53ef\u80fd\u51fa\u73b0\u5947\u5947\u5076\u5076\u7684\u60c5\u51b5\uff0c\u56e0\u6b64\u4e5f\u4e0d\u4f1a\u51fa\u73b01\u30019\u30018\u30018\u3002
解得：
x=3/2; y=9/4
就是说：1/x=y/x=（81/8）/y。由1/x=y/x,得出y=x平方，然后用x把y代掉，问题迎刃而解
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