计算 lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4

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计算 lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4

计算 lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4
计算 lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4

计算 lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4
lg1∕2-lg1∕8+lg12.5-log8为底9乘以log3为底4
=【 lg1∕2-lg1∕8+lg12.5】-log8为底9乘以log3为底4
=lg(1/2÷1/8×12.5)-lg9/lg8×lg4/lg3
=lg50-lg3²/lg2³×lg2²/lg3
=lg50-3lg3/(2lg2)×2lg2/lg3
=lg50-3
=lg(10²÷2)-3
=lg10²-lg2-3
=-1-lg2