设a,b是任意实数，在实数集R上定义的下列运算，哪个满足消去律
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/8fe7daa028204d39a2138b39d2f9d72d.PNG" /> A: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/386b634b9aca4679881e6341dccc8f05.PNG" /> B: f(x)=1 C: f(x)= -1 D: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/8b275b97e5fb4087b7f6018fbcf73ec0.PNG" />
- <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/c3b75de7a0ff4216a7c936dfa863e921.PNG" /> A: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/9bc090082ac447aab731646e7ce4a372.PNG" /> B: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/5666843a7db64c75a2ec586b2db2f35f.PNG" /> C: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/fd98481c51284a9db6d3c21bd7fa60ca.PNG" /> D: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/6f7725736cf84d439343d0c213a650e7.PNG" />
- <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/9b4d8d9a44a447c2af0bf584f998415d.PNG" /> A: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/189e9a57dc014ea8900a1c5f439cd232.PNG" /> B: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/674e45e808174455ad0e186c323d1505.PNG" /> C: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/d383f19ca7094dfdaaa9c71c2b63d924.PNG" /> D: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/995fe28645a0486cbcd43885cdc51a76.PNG" />
- 设a,b是任意实数，下列哪些运算在实数集合上满足交换律和结合律（ ）。 A: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/7abe0a0306124ceab072a913194b8fba.png"> B: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/f6a11590c35c4c3992f467e61557e133.png"> C: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/a538e61384b1410dac2d420df39e5641.png"> D: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/4af08209bbf34076b416e035b70663de.png">
- 在6/8拍子中，哪种记谱是规范的？（ ） A: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/1fa00e5363084599af58abfe32d10c81.png" /> B: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/c5c9c50ae1314ab2852159f18cdfc13c.png" /> C: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/2579da4b06c74d1da3717f6a6562e070.png" /> D: <img src="https://image.zhihuishu.com/zhs/teacherExam_h5/COMMONUEDITOR/202104/c548bd12f6d84b92b2964322fad7904e.png" />