Bonjour,
calcul sur les puissances :
nᵃ × nᵇ = nᵃ⁺ᵇ
nᵃ ÷ nᵇ = nᵃ⁻ᵇ
(nᵃ)ᵇ = nᵃˣᵇ
mᵃ × nᵃ = (m×n)ᵃ
1/n = n⁻¹
donc
3⁴ × 5⁴ = (3×5)⁴⁺⁴ = 15⁸
(5³)⁻² = 5³ˣ⁽⁻²⁾ = 5⁻⁶
2³/2⁻² = 2³⁻⁽⁻²⁾ = 2⁵
(-7)³ × (-7)⁻⁵ = (-7)³⁺⁽⁻⁵⁾ = (-7)⁻²
6⁵/2⁵ = (6/2)⁵ = 3⁵
((3⁴)⁷/(2²⁸×5²⁸) = (3⁴ˣ⁷)/(2×5)²⁸ = 3²⁸/10²⁸ = (3/10)²⁸
(5¹²/5³⁸) × (3¹³)⁻² = 5¹²⁻³⁸ × 3¹³ˣ⁽⁻²⁾ = 5⁻²⁶ × 3⁻²⁶ = (5×3)⁻²⁶ = 15⁻²⁶
1/(1/5⁸) = 1/(5⁻⁸) = (5⁻⁸)⁻¹ = 5⁽⁻⁸⁾ˣ⁽⁻¹⁾ = 5⁸
