Think outside the Box | Learn how to solve this problem without using a calculator

[@KAvi_YA666]

Thanks for video.Good luck sir!!!!!!!!!!!!!

[@PreMath]

So nice of you Thank you! Cheers! 😀

[@j.r.1210]

I used basically the same approach, but maybe saved a step along the way. I just multiplied 3x5x17 mentally to get 255, so immediately I had (256 - 1)*(256 + 1), and the rest followed easily.

[@1960sksrn]

Very much systematic. Application of algebra is marvelous

[@zsoltszigeti758]

3*5*17*257 in binary format is: 11*101*10001*100000001 -> 11*101 = 1111 1111*10001=11111111 11111111*100000001=1111111111111111 So we can see that the result of the multiplication is 2^16-1.

[@luciakinska9742]

Nice

[@jesminakter2577]

Outstanding

[@PreMath]

Thanks

[@devapriyaguharoy7745]

Very stimulating.

[@soli9mana-soli4953]

Spectacular!!

[@vara1499]

A problem seemingly tough became easy due to your innovative solution. Thank you for such interesting experience.

[@PreMath]

Glad it was helpful! Thank you! Cheers! 😀

[@e1woqf]

Of course this "problem" has been made up just to resolve like this. It's more a puzzle than a real problem, but still much fun!

[@haroldosantiago819]

Very smart...

[@PreMath]

Thank you! Cheers! 😀

[@alster724]

Very interesting math problem indeed

[@PreMath]

Yes indeed

[@bigm383]

Great to know that we can function without a calculator!🥂❤👍

[@PreMath]

Absolutely!! I'm not anti-technology. However, never rely on technology a lot. Thank you! Cheers! 😀

[@e1woqf]

The numbers in this equation have been carefully chosen, if there were other numbers, perhaps even fractions, it would be much harder.

[@NYlivinginTN]

That's a fun problem that can show students that with a little insight they can do mental math.

[@PreMath]

Well said! Thank you! Cheers! 😀

[@soniamariadasilveira7003]

Com a vossa ajuda e explicação, tudo fica muito fácil.Um grande abraço, professor!

[@PreMath]

Thank you! Cheers! 😀

[@Megadronte]

Super

[@PreMath]

Thanks

[@luciakinska9742]

It's 2. I like it

[@giuseppemalaguti435]

=sqrt16(1+255*257)=sqrt16(1+(2^8-1) (2^8+1))=sqrt16(1+2^16-1)=sqrt16(2^16)=2

[@PreMath]

Thank you! Cheers! 😀

[@ujwalsmanhas1093]

1+(256-1)*(256+1) = 1+256^2-1^2 = 256^2 = 2 ^16. Rest is easy.

[@PreMath]

Thank you! Cheers! 😀

[@sharonmarshall3671]

I just said 3x5=15 and wrote 15 as 16-1 thereby eliminating your first line in your solution.

[@militarymatters685]

2

[@PreMath]

Thank you! Cheers! 😀

[@militarymatters685]

Thank you sir

[@wackojacko3962]

Unlike the summer Solstice today a once a year occurrence...the famous identity (a-b)(a+b)=a²-b² can be used year round.!🙂....a²+b² might equal 🙂...this edited twice now too fix my mistake: a²+b² is wrong.

[@PreMath]

Thank you! Cheers! 😀 (a-b)(a+b)=a²-b²

[@AmirgabYT2185]

2