题目

计算：（+1）+（﹣2）等于（　　）                                                        A．﹣1                         B．1                            C．﹣3                         D．3 答案：A 【考点】有理数的加法．                                                                          【分析】根据异号两数相加的法则进行计算即可．                                          【解答】解：因为（+1）与（﹣2）异号，且|+1|＜|﹣2|，所以（+1）+（﹣2）=﹣1．                     故选A．                                                                                             【点评】本题考查了有理数加法的运算法则：绝对值不等的异号加减，取绝对值较大的加数的符号，并用较大的绝对值减去较小的绝对值．                                                                              

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