I did a write-up on this on reddit

http://www.reddit.com/r/math/comments/2o7642/i_feel_like_a_special_snowflake_i_discovered_a/

Do I have any right to be excited about this? Because online math, the way it taught me how to do this stuff was a very big complicated series of steps that involved a lot more problem manipulation with a formula. (Like 14 steps to find out Continuous & regular compound interest + while under Double Time conditions)

you do realize that you used the exact formula that you claimed to ignore, right? if it's asking how long it takes for it to double, then the initial principal doesn't matter. hence using 2 and "ignoring" the initial 10,000$

my suggestion: perform the algebra first, then do the arithmetic. you (or your friend?) are doing it in the opposite order; you put numbers into the formula immediately, then try to figure out what to do with the numbers afterwards to get the variable you want. instead, do the algebraic manipulation and isolate the variable first. then you just need to put numbers in the calculator once to get your answer.

This post was edited by carteblanche on Dec 3 2014 05:10pm

the double time forumla u stated is just a rearranging the continuous compounding
the answer ur frend got is wrong cuz the question asked for continous compounding

This post was edited by 2wo1ne on Dec 3 2014 05:12pm

I didn't before, but I see it now,

I saw that when he did lots of other steps in order to get to the same spot in which I started, I saw the similarities. I guess doing it this way eliminated a lot of steps, and gave me an answer close enough to satisfy at least 2 decimal places out, and anything I'd run into on my math test tomorrow.



Exp Growth & Decay, and playing around with all of these formulas has so far, been entirely calculator work. Which is why, when I found out this 'accurate enough/easier' way of doing it just on a calculator. I was really excited.

I'm trying to pool my time and resources towards Rational Functions & Asymptotes. I really dislike the factoring, long division & graphing parts of this section. (In order to find things like Oblique Asymptotes & Holes/MissingPoint/RemovableDiscontinuity) etc :\

Thanks for the feedback btw. I just don't do well when there are a ton of steps, and things seem way more complicated than they are. Like in previous sections with f(g(x)) methods. I just saw it was "Place this entire problem, into X for this entire problem" done. They taught it with so many more steps to do one simple task.

This post was edited by Pk_Dibbun on Dec 3 2014 05:22pm

When I needed to get the Continuous compounding answers, all I needed to do was add that 0.03 number I mentioned, to get the answers correct, for at least 2 decimal places is what they asked for online

This post was edited by Pk_Dibbun on Dec 3 2014 05:23pm

use the calculator exactly once per problem.

Notice how he used the calculator multiple times here?



Instead, do your algebra first:
A = Pe^(rt)
A/P = e^(rt)
ln(A/P) = rt
ln(A/P)/r = t
ln(2)/0.05 = t => use calculator here => 13.86

guess what? that algebra is exactly the same for every continuous interest problem that asks you to solve for time. so you only have to solve the equation once for your entire test, then just use the calculator once per problem.

This post was edited by carteblanche on Dec 3 2014 05:34pm

The below picture is one of the problems I solved, and then I opened up the steps and process they want us to do to solve it regularly there on the side.






Ln(2)/0.09 = 7.70163534 solved the continuously part

Then adding 0.03, gives me the answer for the regular compounded interest

This post was edited by Pk_Dibbun on Dec 3 2014 05:51pm

protoss player + tries to cheese at math

checks out

I've dealt with enough bullshit from these AWFUL math online websites that I am willing to do whatever it takes just to pass :| (Pic was from awhile back)

Edit: fixed

This post was edited by Pk_Dibbun on Dec 3 2014 07:06pm