高一数学对数与对数运算，题目如图，求详解，谢谢
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∵log2(3)=a,2^b=7
∴log2(9)=2log2(3)=2a,log2(7)=b
∴log18(63)
=log2(63)/log2(18)
=[log2(9)+log2(7)]/[log2(9)+log2(2)]
=(2a+b)/(2a+1)
log2(3)log3(4)log4(5)log5(6)log6(7)log7(8)
=(lg3/lg2)(lg4/lg3)(lg5/lg4)(lg6/lg5)(lg7/lg6)(lg8/lg7)
=lg8/lg2
=3lg2/lg2
=3
∴log2(9)=2log2(3)=2a,log2(7)=b
∴log18(63)
=log2(63)/log2(18)
=[log2(9)+log2(7)]/[log2(9)+log2(2)]
=(2a+b)/(2a+1)
log2(3)log3(4)log4(5)log5(6)log6(7)log7(8)
=(lg3/lg2)(lg4/lg3)(lg5/lg4)(lg6/lg5)(lg7/lg6)(lg8/lg7)
=lg8/lg2
=3lg2/lg2
=3
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