Question

find the sums given below -5+(-8)+(-11)+.......+(-230) please give the answer step by step please​

Answer 1

Answer: -8930

Step-by-step explanation:first find number of terms bjp=a+(n-1)d.

It will be in '-' sign . As no. of terms cannot be negetive, convert it to positive. Then find Sn through Sn=n/2(a+l).You will get the answer

Answer 2

Answer:

Sn= -8930

Step-by-step explanation:

 (−5) + (−8) + (−11) + ………… + (−230)

Given:

a = −5

l = −230

d = a2 − a1 = (−8) − (−5)

= − 8 + 5 = −3

d= -3

Let −230 be the nth term of this A.P.

l = a + (n − 1)d

−230 = − 5 + (n − 1) (−3)

−225 = (n − 1) (−3)

(n − 1) = 75

n = 76

Sn = n/2 (a + l)

= 76/2 [(-5) + (-230)] = 38×(-235)

Sn= -8930