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#51 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 06:04:53
Hi SmellyMan;
But, admit it, in your early years you often found math annoying when you didn't understand something
Early years! I still find it that way. But I found a trick.
Could you share this little trick of yours?
OK. But you can still evaluate this to get the initial value.
Have you had a look at
http://www.mathsisfun.com/algebra/trigo … index.html
There is a wealth of excellent help here.
Bob
Thank you, I'll be sure to check this out!
#52 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 05:53:09
Did this question start with sines and cosines by any chance?
Bob
It did, the original task I had was:
(cos(7pi/4) - sin(-9pi/2)) / (sin31pi/4 + cos(-16pi/3))
#53 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 05:47:16
hi Smellyman
where you can't never be sure if you calculated it right.
But you can or at least, with high probability.
Evaluate to a decimal the starting expression.
Evaluate again at any step where you are in doubt.
If you get the same answer, it is very likely you have made correct steps.
If it doesn't, you know you've made a mistake.
You can use the same technique to check algebraic steps.
Choose different values for each variable and evaluate the expression at each step.
It is wise not to choose 0 or 1 as their effect on the calculation may not reveal an error.
Bob
What I meant by confusing the right answer is I can never be sure if the number is positive or negative. At least with reference angles, they're just pain for me to deal with...
Also, for example, when you're writing on the test, you usually don't have the time to check your answers. Sure, when you're learning and doing exercises, I always try to get the right answer, but when you're in a hurry, you'll usually go with the first answer you get, unless you sense there is something REALLY, REALLY wrong.
#54 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 05:32:37
Math annoying? You are kidding right?
It was a remark I made about such problems, where you can never be sure if you calculated it right.
I do not find math annoying at all, and I do realise you made a little personal joke there.
But, admit it, in your early years you often found math annoying when you didn't understand something 
#55 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 05:28:31
Thank you very much, I was having so much trouble on my own, I was solving it by anonimnystefy's way, but I probably miscalculated something and just made a bigger mess.
Thank you once again, these angle problems are annoying and you can never be sure of what the right solution can be 
.
Cheers!
#56 Re: Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 05:06:21
hi SmelyMan
is this what you want:
This is exactly what I am trying to solve!
I couldn't put it into mathematical form as I'm not yet used to the interface and the commands, so excuse me for this mess I made.
#57 Help Me ! » In need of a throughout explanation of the following problem: » 2011-10-10 04:45:08
- SmellyMan
- Replies: 71
(sqrt(2)/2 +1)/(-sqrt(2)/2 - 1/2)
Wolfram Alpha shows the result is -sqrt(2), doesn't matter what I do it doesn't seem like I can get the exact result...
Any help, please? ^^
#58 Exercises » A nice little 'problem'. » 2011-03-17 09:06:16
- SmellyMan
- Replies: 1
I went on the maths competition today, and there was an awesome task that went something like this:
You can only fill each letter with one positive normal number(1,2,3,4,5...), and circle of which the number can you get from the following:
K*A*N*G*A*R*O*O
_________________
G*A*M*E
A)1
B)2
C)3
D)5
E)7
So, same letters mean the same number and you can only use each same number only once(ie. If you decide to give K=1, that means no other letter can be 1)
I hope you understand it^^, enjoy solving this interesting 'puzzle'.
#59 Re: Help Me ! » Simultaneous equations » 2011-03-17 08:55:50
I believe this is solved like that:
2xy+y=10
x+y=4
In this case we have to get y or x, I choose y just because it's simpler. y=4-x
And so you insert this in the first equation and work on from there:
2x*(4-x)+4-x=10
I bet you can do rest on your own ^^. Hf!
#60 Re: Help Me ! » I have no idea how this is called in english. Sorry. » 2011-03-17 04:17:40
How did I miss -1. Argh, silly me ^^. Thank you, kind sir! (:
#61 Help Me ! » I have no idea how this is called in english. Sorry. » 2011-03-16 07:01:38
- SmellyMan
- Replies: 3
So I have a function: f(x)=nx^2+2x+n
And I have to put n like that so the function TOUCHES the x axis.
So I went on with this formula:
D=b^2-4ac
And if it touches that means that D=0.
0=4-4(n)(n)
0=4-4n^2
I am completely stumped here on what to do next.
4(1-n^2)=0
I tried this and the result is 1. But there was supposed to be 2 solutions to this problem ^.^. Any help greatly appriciated! Thank you.
#62 Re: Introductions » Hello, fellow people of mathormotian planet! » 2011-03-06 17:28:54
I did say "dog", as of family pet, which is just awesome ^.^
#63 Introductions » Hello, fellow people of mathormotian planet! » 2011-03-06 09:47:28
- SmellyMan
- Replies: 3
No real sense in the title there, I guess. Let me introduce myself, I'm just a 16 year old guy, trying to learn maths as best as possible. One of my favorite subjects! Going to study computer hardware, but for now I'm just going to high school. While streaming these forums for quite some time, I decided to register, and alas, here I am 
. I certainly hope this will be a pleasant experience. Mostly, in my free time, I take care of my dog^.^, play computer games, commentate them(put them on youtube, stuff like that), take walks, and such. Nothing major, occasional swim from here to there.
Have fun and enjoy!