1) 2⁻² - (²/₃)⁻¹= (¹/₂²) - ³/₂ = ¹/₄ - ⁶/₄ = - ⁵/₄2) 2 - (-1,25)² = 2 - (⁵/₄)² = 2 - ²⁵/₁₆ = ³²/₁₆ - ²⁵/₁₆ = ⁷/₁₆3) - ⁵/₄ : (⁷/₁₆)= - ⁵/₄ * ¹⁶/₇ = - ²⁰/₇4) (3⁰ - ¹/₇)⁻¹ =(1 - ¹/₇)⁻¹ = (⁷/₇ - ¹/₇)⁻¹ = (⁶/₇)⁻¹ = ⁷/₆5) - ²⁰/₇ * ⁷/₆ = - ¹⁰/₃6) 15 * 3⁻² = 15 * (¹/₃²)=15 * (¹/₉) = ⁵/₃7) - ¹⁰/₃ + ⁵/₃ = - ⁵/₃ = - 1 ²/₃