Basic Math & Pre-Algebra All-in-One For Dummies (+ Chapter Quizzes Online). Mark Zegarelli
Читать онлайн книгу.target="_blank" rel="nofollow" href="#fb3_img_img_6002fc97-4d0f-5204-b1a7-70d956ba5a59.png" alt="math"/> as “10 to the fifth power” or “10 to the power of 5.”
1 with two 0s | 1 with seven 0s | 1 with twenty 0s |
---|---|---|
|
|
|
Exponents with a base number of 10 are important in scientific notation, which I cover in Chapter 17.
The most common exponent is the number 2. When you take any whole number to the power of 2, the result is a square number. (For more information on square numbers, see Chapter 1.) For this reason, taking a number to the power of 2 is called squaring that number. You can read
Discovering your roots
Earlier in this chapter, in the section, “Switching Things Up with Inverse Operations and the Commutative Property,” I show you how addition and subtraction are inverse operations. I also show you how multiplication and division are inverse operations. In a similar way, roots are the inverse operation of exponents.
The most common root is the square root. A square root undoes an exponent of 2. For example,
You can read the symbol either as “the square root of” or as “radical.” So read
As you can see, when you take the square root of any square number, the result is the number that you multiplied by itself to get that square number in the first place. For example, to find
You probably won’t use square roots much until you get to algebra, but at that point, they become handy.
A. 81. The expression
Q. What is
A. 1,000,000. Using the power of ten rule,
Q. What is
A. 6. To find
Q. What is
A. 16. To find
This is correct, so
19
(a)
(b)
(c)
(d)