
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
Given the hyperbola $C: \frac{x^{2}}{4}-y^{2}=1$ with left and right vertices $A_{1}$, $A_{2}$, and points $P$ and $Q$ on the curve $C$ symmetric about the $x$-axis, and point $M$ at the intersection of lines $A_{1}P$ and $A_{2}Q$.
(1) Find the equation of the trajectory $D$ of point $M$.
(2) Given point $E(0,2)$, and points $A$ and $B$ on trajectory $D$ satisfying $\overrightarrow{EA}=λ \overrightarrow{EB}$, find the range of real values for $λ$.

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