To find the remainder when 20232023isdividedby35wewillusebinomialexpansion,</p><p>Nowrewritingaboveexpressionweget,</p><p>{2023}^{2023} = {\left(2030 - 7\right)}^{2023}</p><p>⇒ {\left(2030 - 7\right)}^{2023} = C0 2023 {2030}^{2023} - C1 2023 {\left(2030\right)}^{2022} \times 7 + . . . . . - {7}^{2023}</p><p>⇒ {\left(2030 - 7\right)}^{2023} = 35k - {7}^{2023};k \in Z.</p><p>[as2030ismultipleof35]
Now remainder will be −72023. Rewriting −72023, we get
−72023=−(73)674×7
=−(73)674×7=−(343)674×7
=−(343)674×7=−(350−7)674×7
=(35k1+7674)×(−7)
So, again using binomial we get remainder as −7×7674
Again rewriting the expression as
−7×7674=−7675
⇒−7675=−(73)225=(350−7)75
Again using binomial we get remainder as
(350−7)75=(−7)75=−(350−7)25
Again using binomial we get remainder as 725.
Now again rewriting (73)8×7=(350−7)8×7
Using binomial remainder will be 79 which can be written as (73)3=(350−7)3,
Using binomial remainder will be −73 which can be written as −343, so remainder will be 350−343=7,
Hence, the remainder when 20232023 when divided by 35 is 7.