Question

Rozwiąż

a)
x²-5x+4>0
b)
-x(x+6)<9


POTRZEBUJĘ NA JUŻ​

Answer 1

a)

x² - 5x + 4 > 0

Δ = b² - 4ac = (-5)² -4 * 1 * 4 = 25 - 16 = 9

√Δ = √9 = 3

a > 0

x ∈ (-∞ , 1) u (4, +∞)

b)

-x(x+6)<9

-x² - 6x - 9 < 0

Δ = b² - 4ac = (-6)² - 4 * (-1) * (-9) = 36 -36 = 0

√Δ = √0 = 0

a < 0

x ∈ (-∞ , -3) u (-3, +∞)