Page 1 of 2
Ch.9sec4
Chapter9sec4
GeometricSequences
Arithmeticsequences–commondifferencebetweenconsecutiveterms.
GeometricSequence–commonratiobetweenconsecutiveterms.
Page730
Comparetwosequences
ArithmeticSequence
GeometricSequence
5,8,11,14,...
3,12,48,192,...
commondifference
commonratio
Patternforthegeneralterm
Considertheexponentialfunctionandthegeometricsequence
Comparethegraphs.
Math114
Page 2 of 2
Ch.9sec4
Math114
Page731:Example1
Determinewhetherornoteachofthefollowingsequencesisgeometric.Ifthesequenceis
geometric,findthecommonratio,‘r’.
a)6,18,54,162,486,...
b)5,7,9,11,13,15,...c)2.5,6.25,15.625,39.0625,97.65625,...
Page732:Example2
Determinewhetherornoteachsequenceisgeometric.Ifthesequenceisgeometric,findthe
generalterm, an a)6,9,13.5,20.25,30.375,...
b)6,-18,54,-162,486,...
Page735:Example4
Findthegeneralterm, an ,forthegeometricsequenceswiththegiventerms.
a) a4 = 250 ,and a7 = 31,250 b) a2 = −60 and a4 = −15 ,r<0