Standard
Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., \pi^2). <span class='clarification'>For example, by truncating the decimal expansion of \sqrt{2}, show that \sqrt{2} is between 1 and 2, then between 1.4 and 1.5, and explain how to continue on to get better approximations.</span>