Page 24 - Math SL HB Sem 1
P. 24
SEOIIENCB AND S ES
GEOMET'RIC MEAN
Definition: If a, b , c are 3 consecutive terms in a geometric sequence, then
b: J;
is the geometric mean for a and c.
Prove: Given a, b, c are 3 consecutive terms in a geometric sequence,
-bc
Thcn common ratlo,r= -=
ab
b2=ac
b= J;
llxarnple I: Find the geometric mean between t/z and gl9.
Ilxarnpl e 2: Find five geometric means that lies betrveen 4 and 2916.
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