Question
-3, 12, -48, ... Write the explicit and recursive formulas for the geometric sequence. Use your explicit formula to calculate the 6th term in the sequence.
Answers
Reiny
looks like you are multiplying the current term by -4 to get the next term
Now translate "multiplying the current term by -4 to get the next term" into a recursive formula
for the explicit,
a = -3
r = -4
term(n) = a r^(n-1)
= -3(4)^(n-1)
term(6 ) = .....
Now translate "multiplying the current term by -4 to get the next term" into a recursive formula
for the explicit,
a = -3
r = -4
term(n) = a r^(n-1)
= -3(4)^(n-1)
term(6 ) = .....
R_scott
the common ratio is -4
An = -3 * (-4)^(n - 1)
An = -3 * (-4)^(n - 1)