1) (5√2)² - (3√2)² = (25 · 2) - (9 · 2) = 50 - 18 = 32
2) (1/√3)² + (2√3/18) = 1/9 + 12/ 324 = 1/9 + 1/27 = 3/27 + 1/27 = 4/27
3) (a⁻¹² · a⁴) : a⁻⁵ =( a⁻⁸) : a⁻⁵ =a⁻⁸ : a⁻⁵ = a⁻⁸⁺⁵ =a⁻³ = 1/a³ =1 : (1/3)³
= 1 : 1/27 =27
4) ( a⁻⁵)² : a⁻⁶ = a⁻¹⁰ : a⁻⁶ = a⁻¹⁰⁺⁶ = a⁻⁴ = 1 : a⁴ = 1 : ( -1/2)⁴ = 1: 1/16 = 16
5) √36 - √49 = 6 - 7 = - 1
6) √36 · √49 = 6 · 7 = 42
7) 50 · ( - 1/5 √2)² = 50 · 1/25 · 2 = 4
8) ( - 3√5)² + 5(√12)² - (7√5)² = 9 · 5 + 5 · 12 - 49 · 5 = 5 · (9 + 12 - 49) =
= 5 · ( - 28) = - 140
9) √3+√36 = √3+6 = √9 = 3
10) √72 -√64 = √72 - 8 = √64 = 8
11) √4·5²-6² = √4·25-36 = √100-36 = √64 = 8
12) ( 3√5)² : 15 =( 9 · 5) : 15 = 45 : 15 = 3
13) 6 : (2√3)² = 6 : (4 ·3) = 6 : 12 = 1/2
14) (√3)² : 18 = 3 : 18 = 1/6