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The digit in the unit's place of the number represented by (795−758)(7^{95} - 7^{58}) is

Solution

✅ Correct Option: 2

Since we only need the unit's digit, patterns in powers of 7 matter:

Unit's digit in powers of 7 follows pattern: 7,9,3,1,7,9,3,1,... and so on (cycles every 4 powers)

For 7587^{58}:

58 mod 4 = 2

So 7587^{58} ends in same digit as 727^2 = 49, which is 9

For 7957^{95}:

95 mod 4 = 3

So 7957^{95} ends in same digit as 737^3 = 343, which is 3

Therefore, 795−7587^{95} - 7^{58} ends in (..3−..9)=..4(..3 - ..9) = ..4

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