Question

Write the next two terms of the A.P. :

`sqrt5, sqrt20, sqrt45, .......`

Answer 1

Here, a = `sqrt5,` d = a₂ − a₁ = `sqrt20 - sqrt 5`

= `2sqrt5 - sqrt5`

= `sqrt5`

a₄ = a + 3d = `sqrt5 + 3sqrt5 = 4sqrt5 = sqrt(4 xx 4 xx 5)`

= `sqrt80`

a₅ = a + 4d = `sqrt 5 + 4sqrt5 = 5sqrt5 = sqrt(5 xx 5 xx 5)`

= `sqrt125`

Hence, the next two terms are `sqrt80 and sqrt125`.