问题
选择题
2loga(M-2N)=logaM+logaN,则
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答案
2loga(M-2N)=logaM+logaN,化为 (M-2N)2=MN (M>2N>0)
可得M2-5MN+4N2=0
即:(
)2-5M N
+4=0解得M N
=4M N
故选B.
2loga(M-2N)=logaM+logaN,则
|
2loga(M-2N)=logaM+logaN,化为 (M-2N)2=MN (M>2N>0)
可得M2-5MN+4N2=0
即:(
)2-5M N
+4=0解得M N
=4M N
故选B.