Question

（1997•昆明）計算（-

2

3

）^-2=（　�。�

• A．-

  4

  9

• B．

  4

  9

• C．-

  9

  4

• D．

  9

  4

Answer 1

分析：根據(jù)有理數(shù)的負整數(shù)指數(shù)次冪等于正整數(shù)指數(shù)次冪的倒數(shù)解答即可．

解答：解：（-

2

3

）^-2=

9

4

．
故選D．

點評：本題考查了負整數(shù)指數(shù)次冪等于正整數(shù)指數(shù)次冪的倒數(shù)的性質(zhì)，熟記性質(zhì)是解題的關(guān)鍵．