下列各式中成立的是( )A.a+(-2b+c-3d)=a+2b+c-3dB.a-(-2b+c-3d)=a+2b-c+3dC.a-2(-2b+c-3d)=a+4
题型:单选题难度:一般来源:不详
下列各式中成立的是( )A.a+(-2b+c-3d)=a+2b+c-3d | B.a-(-2b+c-3d)=a+2b-c+3d | C.a-2(-2b+c-3d)=a+4b+2c-6d | D.a-2(-2b+c-3d)=a+4b-c+3d |
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答案
A、a+(-2b+c-3d)=a+2b+c-3d,错误,a+(-2b+c-3d)=a-2b+c-3d; B、a-(-2b+c-3d)=a+2b-c+3d,正确; C、a-2(-2b+c-3d)=a+4b+2c-6d,错误,a-2(-2b+c-3d)=a+4b-2c=6d; D、a-2(-2b+c-3d)=a+4b-c+3d,错误,a-2(-2b+c-3d)=a+4b-2c+6d; 故选B. |
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