The explicit rule for a sequence is an=7(−4)n−1.What is the recursive rule for the sequence? an=−4(an−1),a1=7 an=−7(an−1),a1=4 an=−7(an+1),a1=4 an=−4(an+1),a1=7
Accepted Solution
A:
The correct answer is
[tex]a_n=-4(a_{n-1}), a_1=7[/tex]
The explicit formula is of the form [tex]a_n=a_1(r)^{n-1}[/tex], where a₁ is the first term and r is the common ratio. Comparing this to our explicit form, we see that r = -4 and a₁ = 7.
The recursive formula is of the form [tex]a_n=a_{n-1}*r[/tex]; using r=-4 gives us [tex]a_n=-4(a_{n-1}), a_1=7[/tex]