几道对数数学题利用对数换底公式化简下列各题1.log2 3 · log3 4 · log4 5 · log5 22.(l

1. log2 3 · log3 4 · log4 5 · log5 2
=lg3/lg2·lg4/lg3·lg5/lg4·lg2/lg5
=1
2. (log4 3 + log8 3)(log3 2+log9 2)
=(lg3/lg4+lg3/lg8)(lg2/lg3+lg2/lg9)
=(lg3/2lg2+lg3/3lg2)(lg2/lg3+lg2/2lg3)
=(5/6)lg3/lg2×(3/2)lg2/lg3
=5/4
3. 2log5 25 - 3log2 64
=4-3×6
=-14
2log5 25· log5 2
=4log5 2