Answer:
an= a1 +(n-1)*4
Step-by-step explanation:
a1 = 1, a2 =5, a3 = 9, a4= 13,... an= ?
we see that each term is getting bigger so usually that will happen because of addition or multiplication-in our case add 4 to previous term
a1 = 1,
a2 = a1+(2-1) 4 = 1+4 = 5,
a3 = a1 + (3-1)*4 = a1+8 = 1 + 8 = 9,
a4= a1 + (4-1)*4 = a1 + 12 = 1+12= 13,
...
an= a1 +(n-1)*4
