Matt McIrvin on Nostr: npub1zdp33…2vqv8 In my poking around about slide rules I learned about a nifty ...
npub1zdp33shl69xr0uq3x8n5gsjykq9upycwh6nqm02c3f6x0frrn0dq42vqv8 (npub1zdp…vqv8) In my poking around about slide rules I learned about a nifty method they used with slide rules, which kind of depends on the way you can use an analog scale to generate a continuum of "guesses" all at once.
It does involve getting the polynomial into a=1 form: x^2 + bx + c = 0. You set up a couple of the scales (D and CI, I think) so that every pair of numbers on them will multiply to c, and then slide the cursor along there until you get to the pair that sum to b. And now you've factored the quadratic. Sounds like it could be generalized to the ac method without too much trouble.
It does involve getting the polynomial into a=1 form: x^2 + bx + c = 0. You set up a couple of the scales (D and CI, I think) so that every pair of numbers on them will multiply to c, and then slide the cursor along there until you get to the pair that sum to b. And now you've factored the quadratic. Sounds like it could be generalized to the ac method without too much trouble.