The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » Inactive » Historia-Matematica

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: [HM] Bombelli: Cube root of Complex Nos.
Replies: 8   Last Post: Feb 19, 2001 5:31 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Prof. Dr. Jochen Ziegenbalg

Posts: 31
Registered: 12/3/04
Re: [HM] Bombelli: Cube root of Complex Nos.
Posted: Feb 14, 2001 5:57 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Wed, 14 Feb 2001, Bonnie Shulman wrote:

> BUT, in actually computing
> the real and imaginary parts of 2 + 11i, I am left evaluating
> cos(arctan 11/2) (or sin of same). Is there a way to compute
> this analytically (series?) so as to get exactly 2 or 1, rather
> than a numerical approximation? [I suspect so, as my calculator
> gives the exact answers.]

Any (hand-held) calculator will hardly be able to give the exact
answer (even if the display seems to say so), nor will be the usual
floating-based programming languages or spreadsheets (due to the
inherent limitations of floating point arithmetic with the usually
implemented constant "word-length"), but using a computer algebra
system usually will do.

Best regards,

Jochen Ziegenbalg, Karlsruhe

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.