극한값 $\displaystyle \lim _ {x \rightarrow 0} {(1+ \tan 2x) ^ {\frac{1} {2x ^ {2} +x}}}$ 은?

• ①$\displaystyle \frac{1} {2}$
• ②$1$
• ③$e$
• ④$e ^ {2}$