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1. Create a UDF (User Defined Function)
To create this Function, execute the following steps
This Will Create A new UDF (User Defined Function) with name isDat() we Can use this As we Required. type in Excel the function = isDat() ,the UDF Comes up in small letter’s to differentiate itself from “tandard Excel Formula.
In Cell B1 Type
= isDat (A1)
It will show result As TRUE