In an AP sixth term is one more than twice the third term. The sum of the fourth and fifth terms is five times the second term. Find the tenth term of the AP
Answers
given , 6th term = 2(3rd term) + 1 ------------(1)
a + (6 - 1)d = 2(a + (3 - 1)d ) + 1
a + 5d = 2a + 4d + 1
-a + d = 1 ------------(1)×3
given , 4th term + 5th term = 5(2nd term)
a + 3d + a + 4d = 5(a + d)
2a + 7d = 5a + 5d
-3a + 2d = 0 ------------(2)
subtracting (1) and (2)
-3a + 3d = 3
-3a + 2d = 0
__________________
0.a + 5d = 3
__________________
so, d = 3/5
and a = -2/5
we know that , 10th term = a + 9d
= -2/5 + 27/5
= 25/5
= 5
Answer:
given , 6th term = 2(3rd term) + 1 ------------(1)
a + (6 - 1)d = 2(a + (3 - 1)d ) + 1
a + 5d = 2a + 4d + 1
-a + d = 1 ------------(1)×3
given , 4th term + 5th term = 5(2nd term)
a + 3d + a + 4d = 5(a + d)
2a + 7d = 5a + 5d
-3a + 2d = 0 ------------(2)
subtracting (1) and (2)
-3a + 3d = 3
-3a + 2d = 0
__________________
0.a + 5d = 3
__________________
so, d = 3/5
and a = -2/5
we know that , 10th term = a + 9d
= -2/5 + 27/5
= 25/5
= 5