Exercice 2 :
1)A = 9 * 3⁴ / 3⁻⁵ * 27
A = 27⁴ / 81⁻⁵
A = -54⁻¹
B = 4⁻² * 2⁴ / 2⁻⁹
B = 8² / 2⁻⁹
B = 6⁻⁷
2) C = 42 * 10⁻³ * 5 * 10⁶ / 3 * 10⁻⁶
C = 42 * 5 * 10⁻³ * 10⁶ / 0.000003
C = 210 * 10³ / 0.000003
C = 210000 / 0.000003
C = 70000
C = 7 * 10⁴
D = 9 * 10⁻⁹ * 2 * ( 10⁻³ )² / 36 * 10⁷
D = 9 * 2 * 10⁻⁹ * 10⁻⁶ / 360000000
D = 18 * 10⁻¹⁵ / 360000000
D = 0.000000000000018 / 360000000
D = 0.00000000000000000000005
D = 5 * 10⁻²³
J'espère t'avoir aidé ! :)
