Find the indiated terms in each of the following A.P.
(i) ` 1, 7, 13, 19 ,…, 301 , a_(10) , a_(20)`
(ii) ` a= 22 , d = - 3, a_(n) , a_(30)`

Explanation

Here , ` a= 1 , d = 6 `
` therefore a_(10) = a + 9d = 1 + 54 = 55`
` a_(20) = a+ 19 d = 1 + 114 = 115`
Here , ` a = 22 , d = - 3 `
` therefore a_(n) = a + (n-1)d = 22 + (n-1) (-3)`
` 22 - 3n + 3 = 25 - 3n `
and ` a_(30) = 25 - 3 xx (30) = 25 - -90 = - 65 `