5. Find a_6 of the geometric sequence: 4, 12, 36,...
Select one:
a. 243
b. 263
7. Find a_9 for the geometric sequence. 5, –20, 80, ...
a. 327,380
b. 327,680
5. The common ratio is 3 and the first term is 4
So
The 6th term is 4 (3) ^(6 - 1) = 4 (3)^5 = 4 *243 = 972
6. The common ratio is -4 and the first term is 5
The 9th term is 5 (-4)^(9 - 1) = 5(-4)^8 = 327680
