Question

the sum of n terms of an ap is 3n
${3}^{2}$
2 +5n/2 and common difference is 3 whatvis the first term​

Answer 1

Sum of n terms sahi se likho

Answer 2

Answer:

solved

Step-by-step explanation:

S = 3n'2+5n/2 & common difference is 3.

S = 3n²+5n/2 = n/2 ( 5 +6n) = n/2 ( 5 +6n -6 +6 ) =  n/2 { 11 +6(n -1 )}

= n/2{2a+(n-1)d}

comparing

a = 11/2

an other solution

s(n) =  3n²+5n/2

s(1) =  3+5/2 = 11/2