x^2-x+1>0
Let's solve in ℝ: x2 -x + 1 > 0
Given the quadratic form ax2 + bx + c, you can calculate the discriminant: Δ = b2 -4ac. Here a = 1, b = -1 and c = 1
Δ = (-1)2 -4·1·1
ⓘ Powers are computed before multiplications, additions and subtractions. An integer power is a repeated product: (-1)2 = (-1)·(-1) = 1
Δ = 1 -4
ⓘ Start from 1 and move back 4 on the number line, going below zero: 1 -4 = -3
Δ = -3
The quadratic has no real root: it has the sign of a = 1 everywhere, so it is indeed positive for every x.
▶Solution found: x ∈ ℝ