Question

If the sum of the first 50 terms of an Ap is equal to the sum of the first 100 termsl of the same Ap then find the sum of the first 150 terms of the Ap

Answer 1

Answer:

sum of n terms in AP can be given by (n/2)*[2a+(n-1)d]

sum of first 50 terms = 25*[2a+49d]

sum of first 100 terms = (50)*[2a+99d]

sum of first 50 terms = sum of first 100 terms

25*[2a+49d] = (50)*[2a+99d]

2a + 49d = 2* (2a + 99d)

2a + 49d = 4a + 198d

2a =  -149d

s150 =  (n/2)*[2a+(n-1)d]

        = 75 * ( -149d + 149d)                 {2a = -149d}

        = 75*0

        = 0

MARK BRAINLIEST