6. Find the 10th term of an A.P., if the sum of its
third and eighth terms is 7 and the sum of the
seventh and the 14th terms is -3.
Answers
Answered by
2
Answer:
T4 = a+3d
T6 = a+5d
a+3d + a+5d = 42
2a + 8d = 42
a+4d = 21
T3 = a+2d
T9=a+8d
a+2d + a+8d = 52
2a + 10d = 52
a+5d = 26
a+4d = 21
a+5d = 26
d = 5
so a=1
sum of T1-T10 = 10/2(1+46) = 235
AP = 1 6 11 16 21 26 31 36 41 46 . . .
Similar questions