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问题: 帮帮忙哦 一道数学题

利用对数的换底公式化简:(log4 3+log8 3)(log3 2+log9 2) 【注:底数一时不知道该怎样打出来,各位高手应该明白我的题意了!帮帮忙,让我们一起学习哦,先谢了】

解答:

log4 3 = lg3 / lg4 = lg3 / (2lg2)
log8 3 = lg3 / lg8 = lg3 / (3lg2)
log3 2 = lg2 / lg3
log9 2 = lg2 / lg9 = lg2 / (2lg3)

原式 = [lg3/(2lg2)+lg3/(3lg2)][lg2/lg3+lg2/(2lg3)]
   = [(5lg3)/(6lg2)][(3lg2)/(2lg3)]
   = 5/4