Thread: Inequality :\

Stupid inequality i can't solve, we've been told to show a certain method when solving the question which i don't understand T_T

Question


The method we are meant to use is supposed to involved these if statements (4 of them)

1. If (x+4)(3x-2) are +ve then ans is ....
2. If (x+4)(3x-2) are -ve then ans is ....
3. If (x+4) is +ve and (3x-2) is -ve then ans is ....
4. If (3x-2) is +ve and (x+4) is -ve then ans is ....

I think i can do the 1st if statement

If both denominators +ve multiply both sides by (x+4)(3x-2) which results in.




Got no idea how to do 2.3.4 someone help meee

1.

Originally Posted by Kevlar

1. If (x+4)(3x-2) are +ve then ans is ....

The will not change

Originally Posted by Kevlar

2. If (x+4)(3x-2) are -ve then ans is ....

If both terms are negative then the product will be positive and
the will not change.

If is all negative then the will change to

Originally Posted by Kevlar

3. If (x+4) is +ve and (3x-2) is -ve then ans is ....

The will change to as the product is negative

Originally Posted by Kevlar

4. If (3x-2) is +ve and (x+4) is -ve then ans is ....

The will change to as the product is negative

Ok ima try the 2nd and 3rd ones then

2. If (x+4) and (3x-2) are -ve then


is multiplied on both sides by -(3x-2).-(x+4)





???? :z graphs dont intersect if both are +ve or both are -ve? :z

3. If (x+4) is +ve, (3x-2) is -ve.


is multiplied on both sides by -(3x-2).(x+4)





i think ive gone wrong arghttt