A.4 Rational Expressions ??????

1
A.4 Rational Expressions??????
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2
Vocabulary

• ??????????????
• The set of real numbers for which an algebraic
  expression is defined is the domain of the
  expression.
• ????????
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  ???????????????????????????
• ???????
• Algebraic ?????? ???????
• Domain ?????? ??? , ???????

????? ???????????? precalculus ???? A36
3
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ysis) ?????????????????????????????????????
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"???????" ????????????????????????????????????????
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( ????? http//th.wikipedia.org/wiki )
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Vocabulary

• ??????????????
• The quotient of two algebraic expression is a
  fractional expression .
• ????????
• ???????????????????????????????????
  ????????????????????????
• ???????
• Quotient ?????? ?????
• Fractional ?????? ???????

????? ???????????? precalculus ???? A36
5
Vocabulary

• ??????????????
• Moreover, the quotient of two polynomials .
• ????????
• ?????????????????????????????????????????????????
  ?????
• ???????
• Polynomial ?????? ?????????????????????????
  ??????????

????? ???????????? precalculus ???? A36
6
Vocabulary

• ??????????????
• This definition provides an efficient way of
  adding or subtracting two fractions that have no
  common factors in their denominators.
• ????????
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• ???????
• Common factor ?????? ?????????????

????? ???????????? precalculus ???? A38
7
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????????????????? 12,18,24 ????????????
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????????????? ?????? ??????? ???????? 365 ??
???????????? ????????????????????????????????? 300
 ???????????? ???????????????????????????????? The
Elements 
(????? http//iam.hunsa.com/tanita6401/article/218
1)
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Vocabulary

• ??????????????
• Fractional expression with separate fractions
  in the numerator, denominator, or both are called
  complex fractions.
• ????????
• ??????????????????????????? ????????????????
  ??????????????????????????????
• ???????
• Numerator ?????? ???
• Denominator ?????? ??????
• Complex fraction ?????? ?????????????????

????? ???????????? precalculus ???? A40
9
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4/3?????? 11