Question

the sum of n terms of an A.P is 5n square-3n. Find the A.P hence find its 10 term.

Answer 1

Here let n =1 thn on putting the value in eq.1 u will find tht s1 is 2. . follow the same in eq. 2 thn calculate the c.d .. Now you've got both first term and c.d .. So u can calculate the 10th term.
Thank u.

Answer 2

Hey mate........




Here is your answer.........




In this question, first of all, we need to find the second term and the common difference.
$putting \: n = 1 \\ \\ 5 {n}^{2} - 3n = 5 - 3 = 2$




$putting \: n = 2 \\ \\ 5 {n}^{2} - 3n = 14$





Second term is 14 - 2 = 12




AP is 2 , 12 , 22 , .........




Tenth Term = a + 9 d = 2 + 90 = 92