问题
选择题
下列计算中，正确的是（ ）
A．x•x3=x3
B．x3-x=x
C．x3÷x=x2
D．x3+x3=x6
答案
A、应为x•x3=x4，故本选项错误；
B、x3与x不是同类项，不能合并，故本选项错误；
C、x3÷x=x3-1=x2，正确；
D、应为x3+x3=2x3，故本选项错误．
故选C．
搜题请搜索小程序“爱下问搜题”
下列计算中，正确的是（ ）
A．x•x3=x3
B．x3-x=x
C．x3÷x=x2
D．x3+x3=x6
A、应为x•x3=x4，故本选项错误；
B、x3与x不是同类项，不能合并，故本选项错误；
C、x3÷x=x3-1=x2，正确；
D、应为x3+x3=2x3，故本选项错误．
故选C．
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