Question

1.2. If the first term of an A.P. is -5 and the common
difference is 2, then the sum of the first 6 terms is a
a) 0
(b) 5
c) 6
(d) 15
R [NCERT Exemp.​

Answer 1

Answer:

b

Step-by-step explanation:

6th term = a+5d

a=-5. d= 2

-5+5(2)=-5+10=5

5

Answer 2

Answer:

a=-5

d=2

S6=?

using this formula

Sn=n/2(2a+(n-1)d)

S6=6/2(2×-5+(6-1)2)

S6=3(-10+5×2)

S6=3(-10+ 10)

S6= 3(0)

S6=0