问题
选择题
若M=2a2b,N=3ab2,p=-4a2b,则下列各式正确的是( )
A.M+N=5a3b3
B.N+P=-ab
C.M+P=-2a2b
D.M-P=2a2b
答案
A、M+N=5a3b3,错误,M+N=2a2b+3ab2;
B、N+P=-ab,错误,N+P=3ab2-4a2b;
C、M+P=-2a2b,正确;
D、M-P=2a2b,错误,M-P=6a2b;
故选C.
若M=2a2b,N=3ab2,p=-4a2b,则下列各式正确的是( )
A.M+N=5a3b3
B.N+P=-ab
C.M+P=-2a2b
D.M-P=2a2b
A、M+N=5a3b3,错误,M+N=2a2b+3ab2;
B、N+P=-ab,错误,N+P=3ab2-4a2b;
C、M+P=-2a2b,正确;
D、M-P=2a2b,错误,M-P=6a2b;
故选C.