Q. 74.0( 9 Votes )

# Find the n^{th} term of the AP 1, , ….

Answer :

To Find: n^{th} term of the AP

Given: The series is 1, , , , …

a_{1}=1, a_{2}= and d= –1=

(Where a=a_{1} is first term, a_{2} is second term, a_{n} is nth term and d is common difference of given AP)

Formula Used: a_{n} = a + (n - 1)d

a_{n}= a_{1} + (n - 1)( ) = 1– () = =()

So the n^{th} term of AP is equal to ()

Rate this question :

There are n A.M.s between 3 and 17. The ratio of the last mean to the first mean is 3 : 1. Find the value of n.

RD Sharma - MathematicsIf x, y, z are in A.P. and A_{1}is the A.M. of x and y, and A_{2} is the A.M. of y and z, then prove that the A.M. of A_{1} and A_{2} is y.

Insert 7 A.M.s between 2 and 17.

RD Sharma - MathematicsThe 10^{th} and 18^{th} term of an A.P. are 41 and 73 respectively, find 26^{th} term.

If 10 times the 10^{th} term of an A.P. is equal to 15 times the 15^{th} term, show that the 25^{th} term of the A.P. is Zero.

Insert five numbers between 8 and 26 such that the resulting sequence is an A.P

RD Sharma - MathematicsThe 4^{th} term of an A.P. is three times the first and the 7^{th} term exceeds twice the third term by 1. Find the first term and the common difference.

In an A.P. the first term is 2, and the sum of the first 5 terms is one-fourth of the next 5 terms. Show that 20th term is - 112

RD Sharma - MathematicsInsert 4 A.M.s between 4 and 19.

RD Sharma - Mathematics