若X1满足2X+2∧X=5,X2满足2X+2㏒2(X-1)=5,则X1+X2等于( )A5/2 B3 C7/2 D4

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若X1满足2X+2∧X=5,X2满足2X+2㏒2(X-1)=5,则X1+X2等于( )A5/2 B3 C7/2 D4
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若X1满足2X+2∧X=5,X2满足2X+2㏒2(X-1)=5,则X1+X2等于( )A5/2 B3 C7/2 D4
若X1满足2X+2∧X=5,X2满足2X+2㏒2(X-1)=5,则X1+X2等于( )
A5/2 B3 C7/2 D4

若X1满足2X+2∧X=5,X2满足2X+2㏒2(X-1)=5,则X1+X2等于( )A5/2 B3 C7/2 D4
2X+2∧X=5 ==> 5-2x=2^x ==> x1在(1,1.5)之间
2X+2㏒2(X-1)=5 ===> 5-2x=2㏒2(X-1) ==> x2在(2,2.5)之间
所以x1+x2在(3,4)之间
所以选C
作为大题没办法用高中的方法做
如果x2满足2x+log2(x)=5的话,就可以根据2^x和log2(x)互为反函数做