निम्नलिखित सारणी में,रिक्त स्थानों को भरिए,जहाँ AP का प्रथम पद a सार्वान्तर d और n वां पद `a_n` है:

Explanation

यहाँ ` " " a=7,d=3 ,n=8`
` therefore " " a_n =a+(n-1)d`
` " " =7+(8-1)*3`
` " " =7+7xx3 =28`
अतः `" "a_n =28`
(ii) ` " " a=-18,n =10,a_n =0`
` therefore " " a+(n-1)d=a_n`
` rArr" "-18 +(10-1)d=0`
` rArr " " 9d=18 " " rArr " " d=2`
(iii)` " " d=-3,n =18 ,a_n =-5`
` therefore " " a+(n-1)d =a_n`
`rArr a+(18-1) (-3)=-5 " " rArr " " a-51 =-5`
` " "a=-5+51=46`
(iv) ` " " a=-18.9,d=2.5,a_n =3.6`
`therefore " " a+(n-1)d=a_n`
` rArr " " -18.9 +(n-1) xx2.5 =3.6`
` rArr" " (n-1) xx2.5 =3.6 +18.9 =22.5`
` rArr " " n-1 =(22.5)/(2.5) =9rArr n=9+1 =10`
(v) ` a=3.5,d =0,n=105`
` therefore " " a_n=a+(n-1)d=3.5+(105-1)xx0 `
` " " =3.5`