Odpowiedź:
2/b
- 1/4x²+ 3/4x + 1 ≥ 0 / * 4
- x² + 3x + 4 = 0
a = - 1, b = 3, c = 4
Δ = b² - 4ac = 3² - 4 * ( - 1) * 4 = 9 + 16 = 25
√Δ = 5
- b - √Δ - 3 - 5
x₁ = -------------- = -------------- = - 8/ - 2 = 4
2a 2 * (- 1)
- b + √Δ - 3 + 5
x₂ = --------------- = ------------ = 2/ -2 = - 1
2a 2 * (- 1)
5c
2x²- 7x - 4 ≤ 0
2x² - 7x - 4 = 0
a = 2, b = - 7, c = - 4
Δ = b² - 4ac = (- 7)² - 4 * 2 * (- 4) = 49 + 32 = 81
√Δ = 9
- b - √Δ -(- 7) - 9 7 - 9
x₁ = --------------- = ------------ = --------- = - 2/4 = - 1/2
2a 2 * 2 4
- b + √Δ 7 + 9
x₂ = -------------- = ----------- = 16/4 = 4
2a 2 * 2
Szczegółowe wyjaśnienie:
