Answer:
[tex](a)\ u \le -4[/tex]
[tex](b)\ u =\{-\infty,.....,-6,-5,-4\}[/tex]
Step-by-step explanation:
Given
[tex]-u \ge 4[/tex]
Solving (a): An equivalent inequality
We have:
[tex]-u \ge 4[/tex]
Multiply both sides by -1 (this changes the inequality)
[tex]-u*-1 \le 4 * -1[/tex]
[tex]u \le -4[/tex]
Solving (b): Values of u from least to greatest
[tex]u \le -4[/tex] implies that u ends at -4, starting from negative infinity
So, the list is:
[tex]u =\{-\infty,.....,-6,-5,-4\}[/tex]