設集合A={(x,y)|3x+y=1},B={(x,y)|a^2x+3y=a},若A交B=空集,則a=_________

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設集合A={(x,y)|3x+y=1},B={(x,y)|a^x+3y=a},若A∩B=Φ.則a=_________ 解:若A∩B=Φ.3x+y=1與a^x+3y=a是兩條平行線∴3/a^=1/3≠1/a由3/a^=1/3可得:a=±3…①由1/3≠1/a可得:a≠3…②∴由①②可得:a=-3