You have followed the correct steps when you have differentiated the function and then you have tried to solve `f'(x)=0.`

Notice that the equation you need to solve is transcedental, hence you should use numerical or graphical methods to find the roots.

You should consider two functions such that:

`g(x)=x^4 and h(x) = 5^(x-1)*ln 5`

You need to sketch the graphs of these functions and the roots of the equation g(x)=h(x) represent the x coordinates of the points of intersection of graphs.

**Notice that x coordinate of point of intersection between the red and black curves is in `(1,2), ` hence the function reaches its extreme point at a value of `x in (1,2).` **

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