All the Math You'll Ever Need, 3rd Edition

16Powers and Roots

When we use the same number several times in a multiplication, it's convenient to have a shorthand to express it. Another way of writing 2 × 2 × 2 × 2 is 2⁴, or 2 to the fourth power. It's a time-saver for a small number of repeats, but nearly essential if, say, you wanted to multiply 10 or 20 copies of a number. (In algebra, this will be extremely important, but more on that later.)

You may have noticed in past chapters that we often ask you to work backwards, and we will do that again here, in a process called finding a root. It's a bit complicated when you're talking powers and roots, and we'll focus on estimation for much of our conversation on roots. Calculators will be helpful for finding both large powers and for ...