Some students prefer Method 1 for problems like Example 2,which is the
quotient of two fractions. They will use Method 2 for problems like Examples 1,
3, 4, and 5,which have sums or differences in the numerators, or denominators,
or both.Deciding on a Method and Simplifying Complex Fractions
Simplify each complex fraction.(a)Distributive propertyFundamental propertyDistributive property= Combine like terms.3 y+ 2
y+ 8=
y+ 2 + 2 y
4 y+ 8 - 3 y=
11 y+ 22 + 2 y
41 y+ 22 - 3 ya1
y
b y 1 y+ 22 +a2
y+ 2
b y 1 y+ 22a4
y
b y 1 y+ 22 - a3
y+ 2
b y 1 y+ 22=
a1
y
+2
y+ 2
b#y 1 y+ 22a4
y3
y+ 2
b#y 1 y+ 22=
1
y+
2
y+ 2
4
y3
y+ 2EXAMPLE 6452 CHAPTER 7 Rational Expressions and Applications
Be careful not to use as the LCD. Because yappears in two denominators, it
must be a factor in the LCD.y+ 2There are sums and differences
in the numerator and denominator.
Use Method 2.Multiply numerator and
denominator by the LCD,
y 1 y+ 22.(b)Distributive propertyFactor.= Divide out the common factor.x+ 1
x- 2=
1 x- 321 x+ 12
1 x- 321 x- 22=
x^2 - 2 x- 3
x^2 - 5 x+ 6a 1 -
2
x- 3
x^2
bx^2a 1 -
5
x+
6
x^2bx^2=
1 -
2
x- 3
x^2
1 -5
x
+6
x^2There are sums and differences
in the numerator and denominator.
Use Method 2.Multiply numerator and
denominator by the LCD, x^2.http://www.ebook777.com
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