北師大版數(shù)學七年級下冊同底數(shù)冪的除法 鞏固練習 (含答案)

PAGE【鞏固練習】一.選擇題1.（2020?桂林）下列計算正確的是（）A．SKIPIF1<0SKIPIF1<0B．SKIPIF1<0÷SKIPIF1<0=SKIPIF1<0 C．SKIPIF1<0+SKIPIF1<0=SKIPIF1<0 D．SKIPIF1<0?SKIPIF1<0=SKIPIF1<02.下列計算中正確的是()．A.SKIPIF1<0 B.SKIPIF1<0C.SKIPIF1<0 D.SKIPIF1<03．近似數(shù)0.33萬表示為（）A．3.3×SKIPIF1<0 B．3.3000×SKIPIF1<0 C．3.3×SKIPIF1<0 D．0.33×SKIPIF1<04．SKIPIF1<0的結果是（）A．SKIPIF1<0 B．SKIPIF1<0 C．2 D．05.．將SKIPIF1<0這三個數(shù)按從小到大的順序排列為（）A．SKIPIF1<0 B．SKIPIF1<0C．SKIPIF1<0 D．SKIPIF1<06.下列各式中正確的有（）①SKIPIF1<0②SKIPIF1<0；③SKIPIF1<0；④SKIPIF1<0；⑤SKIPIF1<0．A．2個 B．3個 C．4個 D．1個二.填空題7.SKIPIF1<0______，SKIPIF1<0＝______．8.SKIPIF1<0__________,SKIPIF1<0__________,SKIPIF1<0______.9．SKIPIF1<0＝______，SKIPIF1<0＝______．10．一種細菌的半徑為0.0004SKIPIF1<0，用科學記數(shù)法表示為______SKIPIF1<0.11．“神威一號”計算機運算速度為每秒384000000000次，其運算速度用科學記數(shù)法表示，為______次/秒．12（2020?江西）若SKIPIF1<0=-2,SKIPIF1<0=-SKIPIF1<0，則SKIPIF1<0=．三.解答題13．（2020吉州）已知SKIPIF1<0=3，SKIPIF1<0=5．求：（1）SKIPIF1<0的值；（2）SKIPIF1<0的值；（3）SKIPIF1<0的值．14．用小數(shù)表示下列各數(shù)：（1）8.5×SKIPIF1<0 （2）2.25×SKIPIF1<0 （3）9.03×SKIPIF1<015.先化簡，后求值：SKIPIF1<0，其中SKIPIF1<0.【答案與詳解】一.選擇題1.【答案】A；【詳解】A、SKIPIF1<0SKIPIF1<0，正確；B、SKIPIF1<0÷SKIPIF1<0=SKIPIF1<0，錯誤；C、SKIPIF1<0+SKIPIF1<0=SKIPIF1<0，錯誤；D、SKIPIF1<0?SKIPIF1<0=SKIPIF1<0b3?b3=b6，錯誤；故選A.2.【答案】C；【詳解】SKIPIF1<0；SKIPIF1<0；SKIPIF1<0.3.【答案】C；【詳解】0.33萬＝3300＝3.3×SKIPIF1<0.4.【答案】C；【詳解】SKIPIF1<0.5.【答案】A；【詳解】SKIPIF1<0，所以SKIPIF1<0.6.【答案】D；【詳解】只有①正確；SKIPIF1<0；SKIPIF1<0；SKIPIF1<0；SKIPIF1<0.二.填空題7.【答案】3；SKIPIF1<0；【詳解】SKIPIF1<0.8.【答案】SKIPIF1<0；【詳解】SKIPIF1<0.9.【答案】SKIPIF1<0；SKIPIF1<0【詳解】SKIPIF1<0；SKIPIF1<0.10.【答案】SKIPIF1<0；11.【答案】SKIPIF1<0；12.【答案】-32；【詳解】解：SKIPIF1<0SKIPIF1<0，SKIPIF1<0=4=﹣32.三.解答題13.【詳解】解：（1）SKIPIF1<0=SKIPIF1<0?SKIPIF1<0=3×5=15；（2）SKIPIF1<0=SKIPIF1<0=SKIPIF1<0=27；（3）SKIPIF1<0=SKIPIF1<0?SKIPIF1<0÷2=SKIPIF1<0×5÷2=．14.【詳解】解：（1）8.5×SKIPIF1<0＝0.0085（2）2.25×S