If `x^2+2a x+a<0AAx in [1,2],` the find the values of `adot`

Explanation

`x^(2) + 2ax +a lt 0, AA x in [1, 2]`
1 and 2 lie between the roots of the equation `x^(2) + 2ax + a=0`
`rArr" "f(1) lt 0 and f(2) lt 0`
`rArr" "1+2a+a lt 0, 4+ 4a + a lt 0`
`rArr" "a lt -(1)/(3),a lt - (4)/(5)`
`rArr" "a in (-oo, - (4)/(5))`