Use a calculator and enter 2, then press the square root key
Use the approximation 1.41421356
Use the Babylonian method with an initial guess and iterate until it stabilizes
Use Newton’s method to solve x² = 2
Use the continued fraction 1 + 1/(2 + 1/(2 + 1/(2 + …)))
Use the decimal expansion 1.4142135623730951
Use the interval 1.4 to 1.5 and refine by squaring values
Use a table of square roots
Use a computer algebra system
Use a scientific calculator’s sqrt function