Multiplying and Dividing Monomials 5-3
A monomial is an expression that is either a numeral, a variable , or a product of numerals and variables with whole number exponents. IF the monomial is just a numeral we call is a constant.
Some examples: 4x3, -7ab, y (1/2)x5 and 2x4y
The following are NOT monomials
1/y, x1/2, x2 +4, y2 + 2y + 4
Multiplying monomials - use the properties of rational numbers and the properties of exponents:
(3x)(4x) = 12x2
(3x2)(-x) = (3x2)(-1x)
= (3)(-1)(x2)(x)
=-3x3
(-3a)(4a2)(-a4 = (-3)(4)(-1)(a)(a2)(a)
=12a7
Dividing is similar-- Use the properties of rational numbers and the properties of exponents:
x5/x2 = x5-2 = x3
4x2/5x7 = (4/5)x2-7 = (4/5)x-5 OR
(4/5x5)
12m5/4m3 = 3m2
BUT
4m5/12m3 = m2/3
Be careful Keep the RULES Separate!! Don't mix up your exponent RULES with what you know previously for rational numbers!!
Monday, November 9, 2009
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment