一道计算题,
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/21 06:38:38
![一道计算题,](/uploads/image/z/3793459-67-9.jpg?t=%E4%B8%80%E9%81%93%E8%AE%A1%E7%AE%97%E9%A2%98%2C)
一道计算题,
一道计算题,
一道计算题,
原式=㏒25·㏒﹙1/16﹚·㏒﹙1/9﹚/﹛㏒2·㏒3·㏒5﹜
=﹙㏒25/㏒5﹚﹛㏒﹙1/16﹚/㏒2﹜﹛㏒﹙1/9﹚/㏒3﹜
=2·﹙﹣4﹚·﹙﹣2﹚
=16
log225×log31/16×log51/9
=(lg25)/lg2×(lg1/16)/lg3×(lg1/9)/lg5
=2lg5/lg2×(lg1-lg16)/lg3×(lg1-lg9)/lg5
=2lg5/lg2×(0-4lg2)/lg3×(0-2lg3)/lg5
=2lg5/lg2×(-4lg2/lg3)×(-2lg3/lg5)
=16
原式=2X4X2=16
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