Question

Write as with frist term 4 and common difference 1/2?

Answer 1

Step-by-step explanation:

Given A.P is

1,−2,−5,−8,....

hence the common difference is given by d=an+1−an

by putting n=1 in above equation

d=a2−a1=(−2)−(1)

d=(−2−1)

d=−3

first term of this A.P is

a1=1

the nth term of this A.P is given by

an=a1+(n−1)d

⟹an=1+(n−1)(−3)

⟹an=1−3n+3

⟹an=4−3n….eq(1)

finding next four terms of A.P

1)     for finding the 5th term of sequence (a5)  put n=5 in eq(1)

⟹a5=4−3×5

⟹a5=4−15

⟹a5=−11

2)    for finding the 6th term  of sequence (a6) put n=6 in eq(1)

⟹a6=4−3×6

⟹a6=4−18

⟹a6=−14

3)    for finding the 7th term of sequence (a7) put n=7 in eq(1)

⟹a7=4−3×7

⟹a7=4−21

⟹a7=−17

4)    for finding the 8th term of sequence (a8) put n=8 in eq(1)

⟹a8=4−3×8

⟹a8=4−24

⟹a8=−20