Question

maths pls solve .....pls​

Answer 1

Answer:

Any sequence is said to be in A.P. if the difference between it's consecutive terms are equal...

e.g. - Let, a,b,c are in A.P

then, b-a = c-b

or, 2b = a+c

its nth term is given by:-

a↓n = a+(n-1)×d

where, a = first term

d = common difference

sum to nth term is given by:-

S↓n = (n/2) [2a+(n-1)×d]

some important equations:-

d = a↓n-a↓(n-1)

a↓n = S↓n-S↓(n-1)

Now, U may proceed to solve the problems...