How do you write the first five terms of the geometric sequence #a_1=5, r=2x#?

1 Answer
Sep 27, 2017

Answer:

#5, 10x, 20x^2,40x^3,80x^4#

Explanation:

Given
#color(white)("XXX")a_1=5#
By definition of geometric sequence
#color(white)("XXX")a_n=a_(n-1)xxr#
Therefore
#color(white)("XXX")a_2=a_1xxr=5xx2x=10x#

#color(white)("XXX")a_3=a_2xxr=10xx2x=20x^2#

#color(white)("XXX")a_4=a_3xxr=20x^2xx2x=40x^3#

#color(white)("XXX")a_5=a_4xxr=40x^3xx2x=80x^4#