Question

find the sum of all 10 term of A.P whose n term is given by 5n-3​

Answer 1

hope this helps u

if we subsuit n =1,2 the result will the term 1,2

a₁ = 5*1-3= 5-3= 2

a₁₀= 5*10-3=50-3=47

we will use the formula sn= n/2(first term+last term )

                                        s10 = 10/2 ( 2+47)

                                            =  5*49

                                  s10 =  245