Question

please answer this question ​

Answer 1

Step-by-step explanation:

fjjjkffkkfdkkaksskdd

Answer 2

Answer:

sum of first term is 0

Step-by-step explanation:

Given that :-

12

th

term of the A.P is −13

sum of firts four terms is 24

Let, the 1st term of the A.P is a.

and common difference of the A.P is d.

We know, the formula for nth of an A.P. is ,

t

n

=a+(n−1)d

and, the formula for the sum of n−terms of an A.P. is,

S

n

=

2

n

[2a+(n−1)d]

By the question,

t

12

⇒a+(12−1)d=−13

⇒a+11d=−13

⇒a=−13−11d------(i)

S

4

→

2

4

[2a+(4−1)d]=24

⇒2a+3d=12

⇒a=

2

12−3d

------(ii)

comparing (i) and (ii) we get,

−13−11d=

2

12−3d

⇒−22d+3d=26+12

⇒−19d=38 ⇒d=−2

Now, from (i) we get,

a=−13+22

⇒a=9

Hence, sum of the first 10 terms, is,

S

10

=

2

10

[18+(10−1).(−2)]

=5[18−18]=0