
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
Among the following statements, the correct one is $\boxed{\text{answer}}$ (fill in the blank with the corresponding number(s))

$①$ If the set $A=\{x|kx^{2}+4x+4=0\}$ has only one element, then $k=1$;

$②$ In the same Cartesian coordinate system, the graphs of $y=2^{x}$ and $y=2^{-x}$ are symmetric about the $y$-axis;

$③$ $y=( \sqrt {3})^{-x}$ is an increasing function;

$④$ The odd function $f(x)$ defined on $R$ has $f(x)⋅f(-x)\leqslant 0$.

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