How do you find the missing terms of the geometric sequence: 3,---,---,---,768?

1 Answer
Nov 8, 2015

#12#,
#48#,
#192#

Explanation:

In a geometric sequence you multiply by some number #r# to get to the next term. You can think of each comma as a sign telling you to multiply by #r#.

If we call our missing terms #a,b,c# we know that
#3*r = a#
#3*r*r = b#
#3*r*r*r = c#
aaand
#3*r*r*r*r = 768#
#3*r^4= 768#
#r^4= 768/3#
#r^4= 768/3#
#r^4= 256#
#r= 4#
now we can find #a,b,#and, # c# pretty easily
#a = 12#
#b = 48#
#c = 192#