You can put this solution on YOUR website! is just .
The maximum value will occur when nothing is subtracted from the 3 in f(x), i.e. when x=5.
All other values of x will give f(x)<3, and there is no lower limit to the value of f(x), it will be negative infinity when x=-infinity.
I have dr4awn the graph up to x=5 below.
I hope this helps,
Adam
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