101²52²1003² 98²79² Calculer sans poser dopération et sans calculatrice : 997² ² - 95²52² - 48²31² - 29²

(100+1)² 101² = = ² ² =

(50 + 2)² 52² = = ² ² = 2 704

(1000+3)² 1003² = = ² ² =

(100-2)² 98² = = ² ² = 9 604

(80 - 1)² 79² = = ² ² = 6 241

(1000-3)² 997² = = ² ² =

( )( ) = 100² 1² = = 9 999

(30 + 2)(30 - 2) = 30² 2² = = 896

( )( ) = 1000² 3² = =

105² - 95² = ( ) (105-95) = = 2000

52² - 48² = ( ) ( ) = = 400

31² - 29² = ( ) ( ) = 60 2 = 120