\((1)\)设某批电子手表正品率为\(\dfrac{3}{4}\),次品率为\(\dfrac{1}{4}\),现对该批电子手表进行测试,设第\(X\)次首次测到正品,则\(P(X{=}3)\)等于______
\((2)\) 函数\(f(x){=}\dfrac{\ln x}{x}\)的单调递减区间是______.
\((3)f(x){=}{-}\dfrac{1}{2}x^{2}{+}\ln x\)在\({[}\dfrac{1}{e}{,}e{]}\)上的最大值是______.
\((4)\)已知函数 \(y{=}f(x)(x{∈}R)\)的图象如图所示,则不等式 \({xf}{{{{'}}}}(x){\geqslant }0\)的解集为______ .
![](https://www.ebk.net.cn/tikuimages/2/2018/600/shoutiniao67/fe6bcfd2b19c8ccef1f41d74ece35836.png)