Question

Find the nth term of the following sequences:

a.) 5, 10, 15, 20, …

b.) 22, 18, 14, 10, …

Answer 1

a) This is an arithmetic sequence with $a_1=5,\;d=5.$

$a_n=a_1+(n-1)d=5+5(n-1)=5n.$

b) This is an arithmetic sequence with $a_1=22,\;d=-4.$

$a_n=a_1+(n-1)d=22-4(n-1)=26-4n.$