Question

Find the units digit of :
${8}^{25}$
​

Answer 1

8^25

(8^5)^5

(32768)^5

3000+ 2700 +60+8)^5

So its last digit would be same as 8^5

As Zeroes will neutralize it

8^5

32768

So 8

OR

( 8)^25

( 10-2)^25

its past digit would be same (10 - last digit of 2^25

2^25

(32)^5

(3×10 +2)^5

So 2^5

So 32

So 2

Now 10-2 = 8

✌✌✌Dr.Dhruv✌✌✌✌

Answer 2

Answer:

Given:

Find the units digit of :${8}^{25}$

Required answer:

• Possibilities of units digit of ${8}^{n}$ are 8, 4, 2, and 6. The units digit of ${8}^{n}$ gets repeated for every 4th power of 8.

ஃ Remainder obtained when 25 is divided by 4 is 1.

$↦ {8}^{25} = {8}^{4 \times 6 + 1} = {8}^{1}$

ஃUnits digit of ${8}^{25}$is 8.

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