如果點(diǎn)P(1,2)在反比例函數(shù)的圖象上,這個反比例函數(shù)的解析式是 .
【答案】
分析:設(shè)反比例函數(shù)的解析式y(tǒng)=
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,再根據(jù)題意求得k,即可求得反比例函數(shù)的解析式.
解答:解:設(shè)反比例函數(shù)的解析式y(tǒng)=
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,把點(diǎn)(1,2),代入解析式y(tǒng)=
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,解得k=2,
則反比例函數(shù)的解析式是y=
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,
故答案為y=
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.
點(diǎn)評:本題考查了反比例函數(shù)圖象上點(diǎn)的坐標(biāo)特征,經(jīng)過函數(shù)的某點(diǎn)一定在函數(shù)的圖象上.