|x-a| ≤ 2x mit a>0
\( \sqrt{(x-a)^2} \)≤ 2x|\( ^{2} \)
\(( x-a)^{2} \)≤ 4\( x^{2} \)
\( x^{2} \)-2ax+\( a^{2} \)≤ 4\( x^{2} \)|-4\( x^{2} \)
-3\( x^{2} \)-2ax ≤-\( a^{2} \)|:(-3)
\( x^{2} \)+\( \frac{2}{3} \)ax≥\( \frac{1}{3} \)\( a^{2} \)
(x+\( \frac{1}{3} \)a)^2≥\( \frac{1}{3} \)\( a^{2} \)+\( \frac{1}{9} \)\(a ^{2} \)
(x+\( \frac{1}{3} \)a)^2≥\( \frac{4}{9} \)\(a ^{2} \)|\( \sqrt{} \)
1.)x+\( \frac{1}{3} \)a≥\( \frac{2}{3} \)a
x₁≥\( \frac{1}{3} \)a
2.)x+\( \frac{1}{3} \)a≥-\( \frac{2}{3} \)a
x₂≤-a
