Solve the inequality \(\dfrac{3-z}{z+1} \ge 1.\)
thank you and please help! :)
There are two cases (Guest answered the first one):
Case 1: z + 1 >= 0: ---> 3 - z >= (z + 1)·1
3 - z > = z + 1
2 >= 2z
1 >= z ---> z <= 1 (-inf, 1]
Case 2: z + 1 <= 0: ---> 3 - z <= (z + 1)·1 (change the direction of the inequality
3 - z <= z + 1 because you are multiplying by a
2 <= 2z negative)
1 <= z ---> z >= 1 [1, inf)
The final answer is the union of the two above answers.
hmmm the answer is actually \((-1,1]\)
thanks for trying to help though
\(\dfrac{3-z}{z+1} \ge 1\\~\\ z\ne-1\\ If \;\;z<-1\;\;then\\ 3-z\le z+1\\ -2z\le-2\\ z\ge1\\ \)
z cannot be less than -1 and also greater than +1 so no solution here
\( If \;\;z>-1\;\;then\\ 3-z\ge z+1\\ -2z\ge-2\\ z\le1\\ -1
My latex is not rendering. Maybe it will is itself later???
Here is an image of it:
LaTex
\dfrac{3-z}{z+1} \ge 1\\~\\ z\ne-1\\ If \;\;z<-1\;\;then\\ 3-z\le z+1\\ -2z\le-2\\ z\ge1\\
\text{z cannot be less than -1 and also greater than +1 so no solution here}\\~\\
If \;\;z>-1\;\;then\\ 3-z\ge z+1\\ -2z\ge-2\\
z\le1\\
-1 (-1,1]