Sum of infinite terms of series `3 + 5. 1/4 + 7. 1/4^2 + .... ` is

Sum of 25 terms of the series 1 . 3+2 . 5+3 . 7+.. , is

Sum of infinite terms of the series 1 + 4/7 + (9)/(7^2) + (16)/(7^3) + (25)/(7^4) +……, is

FInd the sum of infinite terms of the series 1/(1.2.3)+1/(2.3.4)+1/(3.4.5).....

Sum of infinite terms of the series cot^(-1) ( 1^(2) + 3/4) + cot^(-1) ( 2^(2) + 3/4) + cot^(-1) ( 3^(2) + 3/4) + ... is

Sum of infinite terms of the series cot^(-1) ( 1^(2) + 3/4) + cot^(-1) ( 2^(2) + 3/4) + cot^(-1) ( 3^(2) + 3/4) + ... is

Sum of infinite terms of the series cot^(-1) ( 1^(2) + 3/4) + cot^(-1) ( 2^(2) + 3/4) + cot^(-1) ( 3^(2) + 3/4) + ... is

The sum of infinite terms of the series 5 - 7/3 + (9)/(3 ^(2)) - (11)/( 3 ^(3))+……..o is

Find the sum to n terms of the following series : 3+5xx 1/4+7xx1/4^2 + .....