Question

sum of first 51 terms of an ap whose second and third terms are 14 and 15​

Answer 1

here is the answer of the question

Answer 2

Answer:

1938

Step-by-step explanation:

2nd term =14

3rd term =15

so, common difference (d)= 15-14=1

∴ 1st term (a)= 14-1 = 13

51st term = a + (n - 1)d = 13 + (51 - 1)*1 = 63

∴ sum of first 51 terms Sn = n/2 [ 1st term + last term]

                                          = 51/2 [13 + 63] = 1938