One for the mathematicians - Roots
One for the mathematicians - Roots
Author
Discussion

Skyedriver

Original Poster:

23,419 posts

312 months

Monday 28th January 2019
quotequote all
Son's homework, I know the 3rd root of 64 is 4 and the 5th root of 32 is 2 and that were the two questions but it got me thinking, how do you work it out for more complex numbers. Is there a straight forward method or just trial and error.....

spikeyhead

20,462 posts

227 months

Monday 28th January 2019
quotequote all
Use logarithms

Skyedriver

Original Poster:

23,419 posts

312 months

Monday 28th January 2019
quotequote all
Yee Gods, Log tables, do they still exist, never used them since HNC in 1974.
Would need re-educating on how to use them

anonymous-user

84 months

Monday 28th January 2019
quotequote all
I believe there is an invention called a 'calculator'smile

bucksmanuk

2,426 posts

200 months

Monday 28th January 2019
quotequote all
Take the log of the number
Divide it by the root required, square root divide by 2, cube root divide by 3, fourth root divide by 4, and so on.
Get the anti-log...
You can do it on some calculators but not all.

Skyedriver

Original Poster:

23,419 posts

312 months

Monday 28th January 2019
quotequote all
OK will have a word with my chum A.B.Acus about that.

I've had a look a log tables (and antilog tables) and haven't got a clue any more about how to use them. Funny how I've forgotten over the last 45 years.