unicornilove wrote:
Answer process is right but choice of answer is wrong?
Following your explanations for rejection of "wrong answers", same can be said for B. Since x is either in x<-5 or -2<x<2
Answer B is also WRONG. X<2 includes numbers such as -3 and -4 which are not part of the validrange...
Following your explanations for rejection of "wrong answers", same can be said for B. Since x is either in x<-5 or -2<x<2
Answer B is also WRONG. X<2 includes numbers such as -3 and -4 which are not part of the validrange...
Bunuel wrote:
OfficialSolution:
If\( (|x| - 2)(x + 5) <0\) , then which of the following must be true?
A.\( x >2\)
B.\( x <2\)
C.\( -2 < x <2\)
D.\( -5 < x <2\)
E.\( x <-5\)
\( (|x| - 2)(x + 5) <0\) means that\( |x| -2\) and\( x +5\) must have the oppositesigns.
CASE 1:\( |x| - 2 >0\) and\( x + 5 <0\) :
\( |x| - 2 >0\) means that\( x <-2\) or\( x >2\);
\( x + 5 <0\) means that\( x <-5\) .
Intersection of these ranges is\( x<-5\).
CASE 2:\( |x| - 2 <0\) and\( x + 5 >0\) :
\( |x| - 2 <0\) means that\( -2 < x <2\);
\( x + 5 >0\) means that\( x >-5\) .
Intersection of these ranges is\( -2 < x <2\) .
So, we have that\( (|x| - 2)(x + 5) <0\) means that\( x <-5\) or[m] -2 < x <
...
If\( (|x| - 2)(x + 5) <0\) , then which of the following must be true?
A.\( x >2\)
B.\( x <2\)
C.\( -2 < x <2\)
D.\( -5 < x <2\)
E.\( x <-5\)
\( (|x| - 2)(x + 5) <0\) means that\( |x| -2\) and\( x +5\) must have the oppositesigns.
CASE 1:\( |x| - 2 >0\) and\( x + 5 <0\) :
\( |x| - 2 >0\) means that\( x <-2\) or\( x >2\);
\( x + 5 <0\) means that\( x <-5\) .
Intersection of these ranges is\( x<-5\).
CASE 2:\( |x| - 2 <0\) and\( x + 5 >0\) :
\( |x| - 2 <0\) means that\( -2 < x <2\);
\( x + 5 >0\) means that\( x >-5\) .
Intersection of these ranges is\( -2 < x <2\) .
So, we have that\( (|x| - 2)(x + 5) <0\) means that\( x <-5\) or[m] -2 < x <
...
Statistics : Posted by Bunuel • on 29 Nov 2021, 04:43 • Replies 8 • Views 2290