Let \( n \ge 2 \) be a natural number and \( f:[0,1]\to \mathbb{R} \) be the function defined by
If \( n \) is such that the area of the region bounded by the curves \( x=0 \), \( x=1 \), \( y=0 \) and \( y=f(x) \) is \( 4 \), then the maximum value of the function \( f \) is _____.
