Question

Помогите пожалуйста

Answer 1

4) 3x – x² = 0

(3 – x) x = 0

x₁ = 0

x₂ = 3

5) 12 – 17x – 5x² = 0

D = 17² + 4·12·5 = 289 + 240 = 529 = 23²

x₁ = (17 – 23) / (–10) = 0,6

x₂ = (17 + 23) / (–10) = –4

6) 7x – 4x² = 15

4x² – 7x + 15 = 0

D = (–7)² – 4·4·15 = 49 – 240 = –191 < 0

x ∉ ∅

7) 5 + n² + 6n = 0

D = 6² – 4·5 = 36 – 20 = 16 = 4²

n₁ = (–6 – 4) / 2 = –5

n₂ = (–6 + 4) / 2 = –1