Answer
$(-\infty, \infty)$; see graph and explanations.
Work Step by Step
Step 1. Rewrite the inequality as $4x^2-4x+1\geq0$ or $(2x-1)^2\geq0$; we can see that the solution is all real numbers.
Step 2. We can express the solutions on a real number line as shown in the figure.
Step 3. We can express the solutions in interval notation as $(-\infty, \infty)$
