Sagot :
Bonjour,
2 × 10⁵ × 7,5 × 10⁶ = (2 × 7,5) × 10⁵⁺⁶
= 15 × 10¹¹
= 1,5 × 10¹ × 10¹¹
= 1,5 × 10¹⁺¹¹
= 1,5 × 10¹²
(3,5 × 10⁻⁶) ÷ (14 × 10⁻²) = (3,5 ÷ 14) × 10⁻⁶⁻⁽⁻²⁾
= 0,25 × 10⁻⁴
= 2,5 ÷ 10 × 10⁻⁴
= 2,5 × 10⁻¹ × 10⁻⁴
= 2,5 × 10⁻¹⁺⁽⁻⁴⁾
= 2,5 × 10⁻⁵
13 × 10²¹ + 2 × 10¹⁹
= 13 000 000 000 000 000 000 000 + 20 000 000 000 000 000 000
= 13 020 000 000 000 000 000 000
= 1,302 × 10²²
4,8 × 10⁻¹⁰ - 2 × 10⁻¹¹
= 0,00000000048 - 0,00000000002
= 0,00000000046
= 4,6 × 10⁻¹⁰
a) 2 *10⁵ * 7.5 * 10⁶ = 2 * 7.5 *10⁵⁺⁶ = 15 * 10¹¹ = 1.5 * 10¹²
b) (3.5/14) * 10⁻⁶⁻⁽⁻²) = 0.25 * 10⁻⁶⁺³ = 0.25 *10⁻⁴ = 2.5 * 10⁻⁵
c) 10¹⁹ (13*10² +2) =10¹⁹ (1300+2) = 10¹⁹ *1302 = 10¹⁹ *1.302 *10³ = 1.302*10¹⁹⁺³ = 1.302 *10²²
d) 10⁻¹⁰ (4.8 - 2 * 10⁻¹) = 10⁻¹⁰(4.8 - 0.2) = 10⁻¹⁰ * 4.6
a. 5,158*10^-2 = 5.158 * 1/100 = 0.05158
b. 3,851*10^1 = 3.851 * 10 = 38.51
c. 7,5*10^8 = 7.5 * 100 000 000 = 750 000 000
d. 4,06*10^-4 = 4.06 * 1 / 10 000 = 0.000406