\((1)\)命题:“\({∀}x{∈}R\),\(x^{2}{+}2x{+}m{\leqslant }0\)”的否定是______ .
\((2)\)已知\(A{=}\{ x{|}x^{2}{-}x{\leqslant }0\}\),\(B{=}\{ x{|}2^{1{-}x}{+}a{\leqslant }0\}\),若\(A{⊆}B\),则实数\(a\)的取值范围是______ .
\((3)\)设函数\(f(x){=}\begin{cases} \overset{x{+}1{,}x{\leqslant }0}{2^{x}{,}x{ > }0} \end{cases}\),则满足\(f(x){+}f(x{-}\dfrac{1}{2}){ > }1\)的\(x\)的取值范围是______ .
\((4)\)若\(a\),\(b{∈}R\),\(ab{ > }0\),则\(\dfrac{a^{4}{+}4b^{4}{+}1}{{ab}}\)的最小值为______ .