Question

calculati |x²-8x+14|mai mare sau egal cu 2

Answer 1

x²-8x+14≥2  sau  x²-8x+14≤-2
x²-8x+12≥0  sau x²-8x+16≤0  ⇔(x-4)²≤0⇔x=4

Δ=64-48=16          
x1=(8-4)/2=2
x2=(8+4)/2=6
x∈(-∞;2]∪[6;∞)∪{4}