Finding square of a number

finding square of a number is tough in sometimes

to find square of a number like 995, 1005, 1001, we have to do some min process to get the value.

its is simplified by using formula like

just changing our numbers into formulas like
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Example 1:  Using formula 1

take 995 :

just write :

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Example 2 :  Using formula 2

take  1005 :

just write :

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Example 3 : Using formula 3

take 72 :

just write :

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