Question

Find an equation for the nth term of a geometric sequence where the second and fifth terms are -21 and 567, respectively.

an = 7 • (-3)n + 1

an = 7 • 3n - 1

an = 7 • (-3)n - 1

an = 7 • 3n

Answer 1

@superhelp101 @aryandecoolest @Moo_Moo17

Answer 2

\[a _{n}= a _{1}r ^{n-1}\]
you know this formula?

Answer 3

\[a _{2}= a _{1} r ^{2-1}=-21\]
\[a _{5}=a _{1}r ^{5-1}=567\]

Answer 4

Now solve for \[a _{1}\] and then substitute in above equation to get value of r

Answer 5

thnku soooo much!!!!

Answer 6

oh! you got it...great!! np) @mayaal