Question

8. Calculați x ^2 dacă: a) x = 3√2-5√2; d) x = 5√24-2√54; b)x= 7√3-3√3;​

Answer 1

Răspuns: [ex 8]

a) x = 3√2 - 5√2

x = -2√2

x² = (-2√2)²

x² = (-2)² × (√2)²

x² = 4 × 2 -› x² = 8

d) x = 5√24 - 2√54

x = 5 × 2√6 - 2 × 3√6

x = 10√6 - 6√6 -› x = 4√6

x² = (4√6)²

x² = 4² × (√6)²

x² = 16 × 6 -› x² = 96

b) x = 7√3 - 3√3

x = 4√3

x² = (4√3)²

x² = 4² × (√3)²

x² = 16 × 3 -› x² = 48