15 Calculer A = 11 x 11 D = 26 x 1001 astucieusement. B = 32 x 9 E = 99 × 99 C = 24 x 101 F = 2,761 x 999 Bonjour pouvez vous m’aider ?

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Calculer astucieusement

A = 11 x 11

A = (10 + 1)(10 + 1)

A = 10 x 10 + 10 x 1 + 1 x 10 + 1 x 1

A = 100 + 10 + 10 + 1

A = 121

D = 26 x 1001

D = 26 x (1000 + 1)

D = 26 x 1000 + 26 x 1

D = 26000 + 26

D = 26026

.B = 32 x 9

B = 32 x (10 - 1)

B = 32 x 10 - 32 x 1

B = 320 - 32

B = 320 - 20 - 12

B = 300 - 12

B = 288

E = 99 × 99

E = (100 - 1)(100 - 1)

E = 100 x 100 - 100 x 1 - 1 x 100 + 1 x 1

E = 10000 - 100 - 100 + 1

E = 10001 - 200

E = 10001 - 1 - 199

E = 10000 - 199

E = 9801

C = 24 x 101

C = 24 x (100 + 1)

C = 24 x 100 + 24 x 1

C = 2400 + 24

C = 2424

F = 2,761 x 999

F = 2,761 x (1000 - 1)

F = 2,761 x 1000 - 2,761 x 1

F = 2761 - 2,761

F = 2758,239