Please Help with this question Solve the rational inequality
Please Help with this question...
Solve the rational inequality indicated using a number line and the behavior of the graph at each zero. 1/x + 3Solution
1 / ( x+ 3) < ( x- 5 ) / (x - 11)
or
1/ ( x+ 3) - (x-5) / (x-11) <0
( x- 11) - (x-5)(x+3) / (x+3)(x-11) < 0
( x- 11 - x^2 + 2x + 15 ) / ( x+ 3)(x-11) < 0
(-x^2 + 3x + 4 ) / ( x+3)(x-11) < 0
critical points are -3 , -1 , 4 , 11
testing the inequality at 5 intervals
---------------- -3 ---------- -1 ----------------4------------11----------
( -infinity to -3) test point -4
(-x^2 + 3x + 4 ) / ( x+3)(x-11) < 0
-4^2 + 3(-4) + 4 / ( -4+3)(-4-11) < 0
true
2nd interval (-3 to -1 ) test point -2
false
3rd interval ( -1 to 4) test point 0
true
4th interval ( 4 to 11) test point 5
false
5th interval ( 11 to infinity ) test point 12
true
solution in interval notation is
( -infinity , -3 ) U ( -1 to 4 ) U ( 11 to infinity )
