Question

-7的絕對(duì)值是

 

，-

1

2

的倒數(shù)是

 

．

Answer 1

分析：利用絕對(duì)值和倒數(shù)的性質(zhì)解題．由絕對(duì)值的性質(zhì)，得出-7的絕對(duì)值；由倒數(shù)的性質(zhì)，可得出-

1

2

的倒數(shù)．

解答：解：|-7|=7，-

1

2

的倒數(shù)是-2．

點(diǎn)評(píng)：此題考查了絕對(duì)值和倒數(shù)的性質(zhì)，要求掌握絕對(duì)值和倒數(shù)的性質(zhì)及其定義，并能熟練運(yùn)用到實(shí)際當(dāng)中．
絕對(duì)值規(guī)律總結(jié)：一個(gè)正數(shù)的絕對(duì)值是它本身；一個(gè)負(fù)數(shù)的絕對(duì)值是它的相反數(shù)；0的絕對(duì)值是0．
倒數(shù)的定義：兩個(gè)數(shù)的乘積是1，我們就稱這兩個(gè)數(shù)互為倒數(shù)．