а) 5¹⁵ × 5⁻¹³ = 5¹⁵⁻¹³ = 5² = 25
б) 3⁻⁹ : 3⁻⁸ = 3⁻⁹⁻⁽⁻⁸⁾ = 3⁻⁹⁺⁸ = 3⁻¹ = 1/3 = 1/3
в) (4⁻¹ )³ = 4⁻¹ˣ³ = 4⁻³ = 1/4³ = 1/64 = 1/64