Réponse :
Explications étape par étape
a^2 - b^2 = (a - b)(a + b)
Bonsoir
Calculer mentalement
A = 103^2 - 97^2
A = (103 - 97)(103 + 97)
A = 6 x 200
A = 1200
B = 97 x 103
B = (100 - 3)(100 + 3)
B = 100^2 - 3^2
B = 10000 - 9
B = 9991
C = 1001^2 - 1000^2
C = (1001 - 1000)(1001 + 1000)
C = 1 x 2001
C = 2001
D= 573^2 - 572^2
D = (573 - 572)(573 + 572)
D = 1 x 1145
D = 1145
E = 52 X 48
E = (50 + 2)(50 - 2)
E = 50^2 - 2^2
E = 2500 - 4
E = 2496
