
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Let the universal set $U=\mathbb{R}$, and the sets $A=\{x|-1\leq x<3\}$, $B=\{x|2x-4\geq x-2\}$.
(1) Find $B$ and $\complement_U(A\cap B)$;
(2) If the set $C=\{x|2x+a>0\}$, and $B\cup C=C$, find the range of the real number $a$.

Present the answer in LaTex format: \boxed{Your answer}
user