find the sum of 2/3+1/9

Re- arrange suitably and find the sum: 5/3+(11)/2+\ (-9)/4+\ (-8)/3+\ (-7)/2

Find the sum of first 14 terms of the sequence -3,3,9,15,…….

Find the sum of (i) 20 terms (ii) n terms of the progression 1,3,5,7,9, ....

Find the sum of: 24 terms and n terms of 2 (1)/(2) , 3 (1)/(3) , 4 (1)/(6) ,5 ,......,

Find the sum of the following geometric series: 2/9-1/3+1/2-3/4+ to\ 5\ terms.

Find the sum of G.P. : 1+3+9+27+ . . . . .. . to 12 terms.

Find the sum of the infinite geometric series 1+3x+9x^2+27x^3+…..

Find the sum of the infinite series 1.3/2+ 3.5/2^2+ 5.7/2^3+ 7.9/2^4+.......oo

Prove that : Find the sum of the infinite series 1+(2)/(3).(1)/(2)+(2.5)/(3.6)((1)/(2))^(2)+(2.5.8)/(3.6.9)((1)/(2))^(3)+......oo

Find the sum of the sequence -(1)/(3),1,-3,9 , . . . . . . . Upto 8 terms.