Question

I need help with number 15

Answer 1

f(n) = 2n - 1

Substituting  n = 3:-

third term = f(3) = 2(3) - 1

= 5  (answer)

Answer 2

f(n) = 2n - 1

for n = 1

2(1) - 1 = 1---------1st term

for n = 2

2(2) - 1 = 3-------2nd term

for n = 3

2(3) - 1 = 5-------3rd term

1,3,5