Find the nth term and hence the 20th term of series `2.4+4.6+6.8+…….. Also find the sum of its 20 terms.

Find the nth term and the sum of n terms of the series 1.2.4+2.3.5+3.4.6+....

Find the nth term and the sum of n term of the series 6+9+21+69+261+ ………………...

Find the (i) nth term and (ii) 12th term of the AP 14, 9, 4, -1, -6, …

Find the 17th term and nth term of GP 2,2sqrt(2),4,8sqrt(2),...

(i) The sum of the first n terms of an AP is ((5n^(2))/(2) + (3n)/(2)) . Find the nth term and the 20th term of this AP. (ii) The sum of the first n terms of an AP is ((3n^(2))/(2) + (5n)/(2)). Find its nth term and the 25th term.

Find the sum of first n terms of an AP whose n^(th) term is 5-6n .find the sum of its first 20 terms

Find the 20th term and the sum of 20 terms of the series: 2xx4+4xx6+6xx8+..........

The 14 th term of an A.P.is twice its 8 th term. If its 6th term is - 8 ,then find the sum of its first 20 terms.