Warm Up Find the product. 1. 5 • 5 • 5 • 5 625 2. 3 • 3 • 3 27 3. (–7) • (–7) • (–7) –343 4. 9 • 9 81

If a number is in exponential form, the exponent represents how many times the base is to be used as a factor. A number produced by raising a base to an exponent is called a power. Both 27 and 33 represent the same power. Exponent Base 7 2

Write in exponential form. Identify how many times 4 is a factor. 4 • 4 • 4 • 4 = 44 B. (–6) • (–6) • (–6) Identify how many times –6 is a factor. (–6) • (–6) • (–6) = (–6)3 Read (–63) as “-6 to the 3rd power or -6 cubed”. Reading Math (–6)2 is not the same thing as -62! (–6)2 = 36. -62 = -36 Very Important Math

Write in exponential form. C. 5 • 5 • d • d • d • d Identify how many times 5 and d are used as a factor. 5 • 5 = 52d4

LOL Moment

Negative Exponents Remember! The reciprocal of a number is 1 divided by that number. Remember!

Evaluate. 5–3 5 1 3 = Write the reciprocal; change the sign of the exponent. 1 5 • 5 • 5 = Find the product of three ’s. 1 5 125 1 = Simplify.

Evaluate. (–10)–3 1 = –10 3 Write the reciprocal; change the sign of the exponent. 1 –10 • –10 • –10 = Find the product of three ’s. 1 –10 –1000 1 = = –0.001 Simplify.

The Zero Power Any number (except 0) raised to the zero power is equal to 1. 1490 = 1

Evaluate 5 – (6 – 4)–3 + (– 2)0. 5 – (6 – 4)–3 + (–2)0 = 5 – (2)–3 + (–2)0 Subtract inside the parentheses. = 5 – + 1 1 8 Evaluate the exponents. = 5 7 8 Add and subtract from left to right.

Any number raised to the first power is always equal to itself. 81 = 8 Did you know? Any number raised to the first power is always equal to itself. 81 = 8 If a number is raised to the second power, we say it is squared. 32 is read as three squared. If a number is raised to the third power, we say it is cubed. 43 is read as four cubed. I Love Exponents!

It’s Hip to be Square!

4. Evaluate x • z – yx for x = 5, y = 3, and z = 6. Lesson Quiz: Part I Write in exponential form. 1. n • n • n • n 4 n 2. (–8) • (–8) • (–8) • (h) (–8)3h 3. Evaluate (–4)4 256 4. Evaluate x • z – yx for x = 5, y = 3, and z = 6. –213 5. Evaluate (2/3)-3 27/8

Lesson Quiz: Part II 5. A population of bacteria doubles in size every minute. The number of bacteria after 5 minutes is 15  25. How many are there after 5 minutes? 480