If the n th term of the A.P .58,60,63........  is equal to the n th term of the A.P -2,5,12.......,find the value on n.

Asked by krcraju1973 | 9th Jun, 2019, 05:38: PM

Expert Answer:

58,60,63........
a1 = 58, d1 = 60 - 58 = 2 where a1 is the first term of A.P. 58,60,63........ and d1 be the common difference.
an = a1 + (n - 1)d1
an = 58 + (n - 1)2  ....(i)
-2,5,12.......
a2 = -2 and d2 = 5 - (-2) = 7 where a2 is the first term of A.P. -2,5,12....... and d2 be the common difference.
an = a2 + (n - 1)d2
an = -2 + (n - 1)7  ....(ii)
According to the question,
58 + (n - 1)2 = -2 + (n - 1)7 
58 + 2 = 5(n - 1)
5(n - 1) = 60
n - 1 = 12
n = 13

Answered by Sneha shidid | 9th Jun, 2019, 07:20: PM