bonjour
A = ( x ⁷)² : x ¹⁵
A = x ¹⁴ : x ¹⁵ = x ⁻¹
B = ( x ⁻⁵ * x ³ ) : x ⁻¹²
B = x ⁻² : x ⁻¹² = x ¹⁰
C = x ⁴ : x
C = x ³
