■ What's the final digit of 7^100? | Modular Arithmetic Q2

Find out how to use Modular Arithmetic to answer the question: What's the final digit of 7^100?

Whilst it looks like an intimidating question, modular arithmetic makes it much more straight forward!

Introduction to modular arithmetic video (Watch this first!):

Find the rest of the videos in this intro to modular arithmetic mini-series here:

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[facts-ecyi]

This helped alot with my uni work. I like the clock analogy. Thank you!

[aku]

Had to search for a long time to find this gem. Hopefully you get more subs and make it to the top of people's recommendation lists!! :)

[darksoul]

Remember guys
Give a like to show your gratitude. She's saving our time and money.

[petermorgan]

Found your videos on modular arithmetic incredibly helpful. The text I'm using is rather stuffy and harder to follow than it should be. Your simple examples, skilfully presented, really cut through all that. What i thought was one of the trickier parts of my abstract maths course now seems almost trivial. Thanks! And keep it up!

[antoniogb]

I’m enjoying theses videos about mod arithmetic so much! Keep it up :)

[hamidturky]

thank you so much your explanation is great and helped me to solve the same question for my task:)

[MrMadCheesecake]

these vids are so good! why dont you have more subscribers?!

[germanrobledo]

You are amazing!!! Thank you. I love your work.

[showkatahmad]

Better to use
7²=49=-1(mod10)
=> (7²)⁵⁰=(-1)⁵⁰(mod10)
=> 7¹⁰⁰=1(mod10)

[PugboyMan]

Great video with amazing explanation, I'm just wondering what you do if you have a odd number for example 9^59

[Problematica.]

7^4 last figure 1. 7^100=(7^4)25 last figure 1

[muhammadfirdaus]

how would you do 2^2019 last digit with this method?

[SachinKumar-fvro]

The remainder of 2020^2020 (mod 7) is equal to 4

[Problematica.]

Find the last three digits of the number 19^97