Question

sum of 1st 'n' terms is given by 5n+7.find sum of 3 terms, 1st term, 15th term, nth term​

Answer 1

Step-by-step explanation:

explanation attached

hope it helps u

Answer 2

1st term = 2nd term & 3rd term.....

Step-by-step explanation:

for my opinion 5 us correct