In the whole of mathematics can you show me a single definition defining the exprssion " small epsilon"?
In the definition of limits we say for all epsilon biger tha 0 ,there exists a delta biger than 0 such that: e.t.c e.t.c
99% of the problems in analysis stert with the expession . Let ε>0, or given ε>0
Yes you can use small or big epsilon,or delta .
But if you do not clearly show their relatin to other variables of the problem or between them it is catastrophic.
In the limits for example ,you have to clearly show the relatio9n between epsilon and delta, whether the epsilon and deltas are small or big,or whatever
In your solution what will happen if for your " small epsion" we have a small : b-a??
Besides when you say : " for a small epsilon ",one may say ,ok But how small .
Mathematics is relations between variables and certainly expressions or words of : small,big ,tiny e.t.c do not show relations