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计算:(log4 9+log8 3)(log3 2+log9 2)-log1/3 4√81

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计算:(log4 9+log8 3)(log3 2+log9 2)-log1/3 4√81
log后面的第一个数都是小数字,最后边是81的4次方根
计算:(log4 9+log8 3)(log3 2+log9 2)-log1/3 4√81
要用到换底公式,以及对数运算法则

log4 9=2/2* log₂3=log₂3
log(1/3)⁴√81=-log₃⁴√81
(log4 9+log8 3)(log3 2+log9 2)-log1/3 (⁴√81)
=(log₂3+1/3*log₂3)(log₃2+1/2*log₃2)-[-1/4* log₃3³]
=(4/3*log₂3)* (3/2*log₃2)+3/4
=4/3*3/2(log₂3)*(log₃2)+3/4
=2+3/4
=11/4