Talk:2070: Trig Identities

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I am confused by the insect line. This seems to be true only if s=t. 19:03, 9 November 2018 (UTC)

I added a note regarding how similar it sounds to 'sinsec'. 01:47, 10 November 2018 (UTC)
That one and the `cas` aren't making any sense to me. GreatBigDot (talk) 20:02, 9 November 2018 (UTC)
Oh, the casinus is much important to... What was it? --Dgbrt (talk) 20:15, 9 November 2018 (UTC)
cas is realtively easy... it is cos(theta)=a/c -> cs(theta)=ao/c -> cas(theta)=o/c; when you realise that the top one isn't zero but o it clicks 23:35, 9 November 2018 (UTC)
You made the same error Randall did: you divided by 'o' on the left and multiplied on the right. I think the theme of the page is expanding significantly upon common math errors that were already humorous, like the common proof of 5=3 by dividing and multiplying by zero. The error here is in line with the theme of casual beginner errors.
You can see cin is derived from sin by swapping the positions of c and s. Likewise, Switching the a and o in cos(theta) = a/c gives cas(theta) = o/c i.e. no need for multiplicative consistency. The rule of treating things as a product of terms is implemented fully in the following lines. 11:23, 12 November 2018 (UTC)
 sin \theta = b/c leading to cin \theta = b/s is algebraically valid if you interpret sin as the product of s, i, n by multiplying both sides by c/s. It is not valid to just "swap" two letters in one equation that is part of a system of equations. You could do the same trick and get cas \theta = a^2/oc from cos \theta = a/c or start with sec \theta = c/a and get cas \theta = c/e. Note for all equations except cas \theta = o/c and switching an s to a t to find tan \theta = insect \theta^2, the equations can be correctly derived by treating trig functions as product of single letter variables and algebraically manipulating them. Jimbob (talk) 16:59, 12 November 2018 (UTC)
I think insect is.. a bug.. ;) Smerriman (talk) 20:18, 9 November 2018 (UTC)

Is Enchant at target a magic:the gathering reference? AncientSwordRage (talk) 20:55, 9 November 2018 (UTC)

I think it is a Magic: The Gathering reference. Although it is phrased oddly. You'd think it would be "at target enchantment", rather than "target at enchantment". --Dryhamm (talk) 21:04, 9 November 2018 (UTC)
Likely, it refers to the bigbox retailer, Target. (talk) (please sign your comments with ~~~~)
To me it sounds more like a reference to a nerdy video game, where a certain object worked like this, turning e.g. BEAM OF DARK ENERGY into a BAKED FERRY GNOME 21:53, 12 November 2018 (UTC)
Voila - s=t. -- Elliott (talk) (please sign your comments with ~~~~)
That was incredible! (assuming previous poster discovered the extrapolated proof in the description) 01:47, 10 November 2018 (UTC)
Combining \cos\theta=\frac{a}{c} and \mathrm{cas}\ \theta=\frac{o}{c} allows you to conclude a^2 = o^2, not a=o. (talk) (please sign your comments with ~~~~)

Somebody added a comment on puns, e.g. that "cin sucks". More explanation is needed. It looks like some kind of a meta-joke. If you ask why, and start interpreting, you see that "b/c" == "because". It might be the answer to why the puns line should be removed, though.

For the Bot->Boat->Stoat line, this comes from the word game where you add/change letters to make a new word. Start with bot=a/c, multiply by a on both sides gets boat=a^2/c. Multiply by st on both sides and divide b on both sides gets Stoat=a^2/c*St/b. (talk) (please sign your comments with ~~~~)

Uh... people... THE NAME GAME? Hello? (talk) (please sign your comments with ~~~~)

Checking through the math, just working from the real trig identities, without considering Randall's at-first-glance questionable identities like cas theta = o/c, basically everything that does not have a factor of d or 2 in it is equal to 1, and d is equal to 1/2, which then establishes the more questionable identities as tautological, 1=1. 04:09, 10 November 2018 (UTC)

\sec\theta = sect \eta 13:36, 10 November 2018 (UTC) AndreasH

Am I the only one who saw t²n²a⁴ as "tuna"? 14:17, 10 November 2018 (UTC)

Yes. (talk) (please sign your comments with ~~~~)

\frac{d}{dx}\sec x=\sec x\tan x= sex tanks. Probably not Douglas Hofstadter (talk) 21:36, 11 November 2018 (UTC)

I thought "distance 2 banana" had to be a reference to QBasic's Gorillas game. "Enchant at target" could refer to the banana exploding when it hits something. mrpsbrk (talk) (please sign your comments with ~~~~)