if the third and the fourth term of an arthmetic progression are 4 and -8 respectively which term of it is zero
Answers
Answer:
10/3 term is 0
Step-by-step explanation:
Given:
a3 = a + 2d = 4
a4 = a + 3d = -8
To find: Which term is zero
an = a + (n - 1)d
Solution:
d = -8-4
d = -12
substitute d = -12 in a3
a + 2(-12) = 4
a - 24 = 4
a = 4 + 24
a = 28
a + (n-1)d = 0
28 + (n-1)-12 = 0
-12n + 12 + 28 = 0
12n + 40 = 0
12n = 40
n = 40/12 = 10/3
10/3 term is 0
Verification:
28 + (10/3 - 1)-12 = 28 + 7/3 × -12
= 28 - 84/3
= 28 - 28
= 0
Hope it helps you:)
Step-by-step explanation:
Given:-
=> a3 = a + 2d = 4
=> a4 = a + 3d = -8
To Find:-
Which term is zero.
an = a + (n - 1)d
Solution:-
d = -8-4
d = -12
substitute d = -12 in a3
a + 2(-12) = 4
a - 24 = 4
a = 4 + 24
a = 28
a + (n-1)d = 0
28 + (n-1)-12 = 0
-12n + 12 + 28 = 0
12n + 40 = 0
12n = 40
n = 40/12 = 10/3
10/3 term is 0
Verification:-
28 + (10/3 - 1)-12 = 28 + 7/3 × -12
= 28 - 84/3
= 28 - 28
= 0