If the domain of the function f(x)= e ( 2 x+34 x2+x-3 )+ -1 ( 2 x-1x+2 ) is ( , ], then the value of 5 -4 is equal to
- 9
- 12
- 11
- 10
Answer
(2) 12
Solution
: 2x+3(4x-3)(x+1)>0 x (- 32,-1 ) ( 34, ) (sign scheme)
-1: 2x-1x+2 1 x-3x+2 0 -2<x 3
and 2x-1x+2 -1 3x+1x+2 0 x<-2 or x - 13
x [- 13,3 ]
[figure]
domain = ( 34,3 ] = 34, =3
5 -4 =15-3=12
Answer: (2)