Exponent Review #1 September 26, 2012
Exponents: Exponents are shorthand for repeated multiplication of the same thing by itself. For example,
53=5∙5∙5=125
(-2)4=-2-2-2-2=16
x5=x∙x∙x∙x∙x
Example 1: Simplify (x3)(x4) Copyright © Elizabeth Stap999-2009 All Rights Reserved
To simplify this, think in terms of what the exponents mean.
x3 means x∙x∙x
x4 means x∙x∙x∙x
Therefore, (x3)(x4) = (xxx)(xxxx)
= xxxxxxx
= x7
Note that x7 also equals x(3+4).
This demonstrates the first basic exponent rule.
RULE 1: Whenever you multiply two terms with the same base, you add the exponents: am∙an=am+n
èNote: We can NOT simplify (x4)(y3), because the bases are different: (x4)(y3) = xxxxyyy = (x4)(y3). Nothing combines.
Simplify the expressions below. If they cannot be simplified, write ‘Not Possible’.
1. aaaaaa / 2. -22 / 3. -224. x3z2 / 5. x3x2x7 / 6. x3y2y9
7. x3y3z2 / 8. x2y4x100y
Example 2: Simplify x5x2Copyright
To simplify this, think in terms of what the exponents mean.
x5=x∙x∙x∙x∙x
x2= x∙x
Therefore,
x5x2=xxxxxxx
=xxxxxxx=xxx=x3
Note that x3 also equals x(5−2). This demonstrates the second basic exponent rule.
RULE 2: Whenever you divide two terms with the same base, you can subtract the exponents:
aman=am-n
RULE 3: Anything to the power zero is just "1": a0=1
9. -20 / 10. -20 / 11. x3 x212. x3z2 / 13. x3x12x4 / 14. x3y22y9
15. x3x0z2 / 16. x200y4x100y / 17. z5x
18. x0y0z0 / 19. x9y9z9x3yz0 / 20. z5z13
Some Information in this worksheet was obtained from :
Stapel, Elizabeth. "Fractional (Rational) Exponents." Purplemath. Available from
http://www.purplemath.com/modules/exponent5.htm. Accessed 22 April 2009Page 1