Q.

The solution of 6x4x-1<12 is

1 x<-18  
2 -18<x<14  
3 x<-18 and x>14  
4 x>18  

Ans.

(2)

Given inequality is, 6x4x-1<12⇒12x4x-1<1

⇒12x4x-1-1<0⇒8x+14x-1<0                 …(i)

For above inequality (i), we have two cases either

(I)  8x+1>0, 4x-1<0  or  (II)  8x+1<0, 4x-1>0

From (I), we get  x>-18, x<14

∴   x∈(-18,14)                                 …(ii)

From (II), x<-18, x>14, both of which can not be true

∴    (ii) represents the solution set of given inequality.