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Grade 12Algebra

Find the last digit and last two digits of 3^73
Use the method of binomial theorem

Profile image of Aditya Gangrade
6 Years agoGrade 12
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1 Answer

Profile image of Saurabh Koranglekar
6 Years ago
Dear student

Last digit can be found using fact that 3 ^x follows unit digit pattern of 3,9,7,1,3...

Therefore last digit is 3

For second last digit

See that 3^ 73 can be written as

3*( 27^ 24)

Now split 27 as 10+ 17

Now find unit digit of the term with 24c1*10*(17^23)

Using this approach we can find the answer kindly tell if the problem still persists

Regards