Question

Rozwiąż równanie x^2 < 2-x

Answer 1

x² < 2 - x

x² + x - 2 < 0

Δ = 1² - 4 * 1 * (-2) = 1 + 8 = 9

√Δ = 3

x1 = (-1 - 3)/2 = -4/2 = -2

x2 = (-1 + 3)/2 = 2//2 = 1

 

a = 1 >  0  więc parabola ma ramiona skierowane do góry

 

++++          ++++

------o------o------>

        -2 ---- 1

odp. x ∈ (-2, 1)