Привет :-)
а) —3⁻⁴ = —(1/3)⁴ = —1/81;
б) —(—5) — 2 = 5 — 2 = 3;
в) (—2)⁻⁴ = (—1/2)⁴ = 1/16;
г) —(—2)⁻⁵ = —(—1/2)⁵ = —(—1/32) = 1/32;
д) 2⁻¹ + 3⁻¹ = (1/2)¹ + (1/3)¹ = 1/2 + 1/3 = 3/6 + 2/6 = 5/6;
е) 2⁻² — 3⁻² = (1/2)² — (1/3)² = 1/4 — 1/9 = 9/36 — 4/36 = 5/36;
ж) 3⁻² + 3⁻³ = (1/3)² + (1/3)³ = 1/9 + 1/27 = 1/9 * (1 + 1/3) = 1/9 * 4/3 = 4/27;
з) 5⁻² — 4⁻² = (1/5)² — (1/4)² = (1/5 — 1/4)(1/5 + 1/4) = (4/20 — 5/20)(4/20 + 5/20) = (—1/20)(9/20) = —9/400.