閱讀兩位同學(xué)的探究交流活動(dòng)過(guò)程:
a.小明在做分式運(yùn)算時(shí)發(fā)現(xiàn)如下一個(gè)等式,并對(duì)它進(jìn)行了證明.
x+2x+3-x+1x+2=1x+2-1x+3;①
b.小明嘗試寫(xiě)出了符合這個(gè)特征的其他幾個(gè)等式:
x+3x+4-x+2x+3=1x+3-1x+4;②
x+4x+5-x+3x+4=1x+4-1x+5;③
x+5x+6-x+4x+5=1x+5-1x+6;④
…
c.小明邀請(qǐng)同學(xué)小亮根據(jù)上述規(guī)律寫(xiě)出第⑤個(gè)等式和第n個(gè)等式(用含n的式子表示,n為正整數(shù));
d.小亮對(duì)第n個(gè)等式進(jìn)行了證明.
解答下列問(wèn)題:
(1)第⑤個(gè)等式是 x+6x+7-x+5x+6=1x+6-1x+7x+6x+7-x+5x+6=1x+6-1x+7;
(2)第n個(gè)等式是 x+n+1x+n+2-x+nx+n+1=1x+n+1-1x+n+2x+n+1x+n+2-x+nx+n+1=1x+n+1-1x+n+2;
(3)請(qǐng)你證明第n個(gè)等式成立.
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【考點(diǎn)】分式的混合運(yùn)算;規(guī)律型:數(shù)字的變化類(lèi).
【答案】-=-;-=-
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【解答】
【點(diǎn)評(píng)】
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發(fā)布:2024/6/27 10:35:59組卷:934引用:4難度:0.5
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