Question
the 2nd term of a progression is -7 and the 5th term is 56.find the common ratio and the sum of the first five terms
Answers
oobleck
ar = -7
r^3 = 56/-7 = -8
Now you can easily fine a and r, and
S5 = a(r^5-1)/(r-1)
r^3 = 56/-7 = -8
Now you can easily fine a and r, and
S5 = a(r^5-1)/(r-1)