Page 24 - Math SL HB Sem 1

SEoUENCE AND S

(;I.]OMT'TRIC MIIAN

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,

Then common rulio, r: !=9

-) b2=ac
b=J;

I3xample I : Find the geometric mean between ,/, and gl9.

Example 2: Find five geometric means that lies betrveen 4 and 2916.

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