This thread is awesome. Taking Elementary Algebra because I’m stupid. Reading up on this may come in handy.
Saw this on facebook, I counted 45, did it again got 36 lol :looney:
http://sphotos-a.ak.fbcdn.net/hphotos-ak-ash4/310302_10151080749089753_1544405990_n.jpg
Not sure how you got 45. I count [S]39 [/S] 40
Big tiles:
16 one-tiled squares
[S]8 [/S] 9 four-tiled squares (thanks MCP)
4 nine-tiled squares
1 sixteen-tiled square
[S] 29 [/S] 30
Small tiles
4*2 one-tiled squares
2 four-tiled squares
10
I’m not so sure…
24 single-tiled squares (16 big + eight small), 11 four-tiled squares (9 big and two small), 4 nine-tiled, and one 16 tiled.
40 total.
I think you missed the one big four-tiled square in the middle of the board.
yep.
Is there a site out that solves questions for ya’?
Doing some work, but merely to study practice problems for a test tomorrow. However, no idea if I’m getting them right or not.
Got something like: 13 < -2/3x + 5
(2/3 being a fraction)
Getting -12 > X
One option: http://www.wolframalpha.com/input/?i=13+<+(-2%2F3)*x+%2B+5
- Better to just figure it out on your own at this point.
- Then once you’ve worked really hard and think you’ve done all the problems correctly
- I suggest trying wolframalpha, but you might get frustrated if you don’t enter it correctly. Use parenthesis generously, e.g. (-2/3)*x + 5 > 13
Thanks for the info.
Basically, I just wanted to know if I had the right answer so I know I’m doing it right, not to cheat on my homework or anything, lol.
Not to mention, all of our homework is review, and test counts a huge part of our main grade.
Man infinity is really stupid… odd question…
x/x^2 as x approaches infinity=0…
Prove this… I was told that it is what it is for the longest time… but it frustrates me that this will become somehow become zero, instead of some infinitely small number that is really, really close to zero…
You can get an idea if it’s right by plugging in a “nice” number. For instance, x = -30 will cancel out that 3 in the demonimator.
What you were told is true, but that function will never become zero.
First off, x/x^2 is the same thing as 1/x, which is this
As you go further along the x axis, the values of y get smaller and smaller, but there is a number that they will not get smaller than, and that number is 0. 0 is that limit. There is no value x that will result in a value of 0. The interpretation is that we may make this function’s y values as close to zero as we please however.
So, another basic algebra question. Ran into something that says:
(something like this, I think)
Sunny was charging $1500 plus 22% for tickets. At the end of the event, she made $3200. How much did she make off the tickets?
How would you write the equation for this?
It’s ok because you can’t actually reach infinity.
This is what limits are all about and why calculus normally starts off with what seems like way too much material covering them. In essence calculus works because that line does get to zero at x=∞. (And this causes me to note that it’s not technically allowed to say x=∞, mathematically you have to say “the limit as x approaches infinity.” But x=∞ is pretty convenient short-hand.)
(To put it another way, if the value could only get arbitrarily close to zero but never reach zero, then calculus would only be able to provide arbitrarily accurate solutions and not exact ones.)
Made this photoshop to double check, each individual box given a letter.
a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y = 25
abef, bcfg, cdgh, efij, fgjk, ghkl, ijmn, jkno, klop = 9
qrst, uvwx, = 2
abcefgijk, bcdfghjkl, efgijkmno, fghjklnop = 4
total= 40
No idea where I got the extra 5 from lol, my mental arithmetic skills are E tier
This is confusing. The value of 1/x does not reach zero and it does only get arbitrarily close to zero. Saying it reaches zero at x=∞ may be convenient shorthand to express a limit (but limit notation with -> is still better), but it’s just notation. It doesn’t change the fact that 1/x is never zero. And calculus can give exact solutions in the theoretical sense that infinite series or sequences converge to some real number, but in practice to actually get a numerical value most times arbitrarily accurate is the best you can do, and this makes no difference because no physical measurement can even reach arbitrary accuracy anyway. Using the contraction mapping theorem to find the inverse of a function in the neighborhood of a point, or using the same theorem to solve a differential equation are a couple of examples.
edit: That square tile problem is nice. There’s a quick way if you know that there are 1^2+2^2+…+n^2 squares on an nxn chessboard, which can be proved by basic combinatorics (for a 2x2 square for instance, there are n-1 vertical lines where the top left corner can go, and n-1 horizontal lines). This is just a chessboard with two smaller chessboards inside it. 1^2+2^2+…+4^2+2(1^2+2^2)=40.
So I’m studying for a calculus test right now and i feel like i hit a wall. How do I take a derivative of y^3 - xy - x^3 =0. I don’t remember working on any problems like this so far so I’m a little stumped.
look in the section on implicit differentiation. Don;t forget to use the chain rule on -xy. Then solve for y’
Kind of a niche thing but I’m looking for an ASCII rendering of Alan Turing if anyone knows of someone who does ASCII art
Don’t forget the apple next to him. England really knows how to reward their heroes.
Tragedy really. I am a budding student of mathematics and also an instructor of systems that draw on fundamentals founded by Turing. I’m not really the emotional type but when I first heard his story it impacted me.
I ran across some fun (maybe?) problems over the past few days online.
-
If 100!=12^n*M (that’s 12 to the nth, times M) where n is the largest integer possible while keeping M an integer, is M divisible by 2? by 3? by 4?
-
Solve (z+i)^n-(z-i)^n=0
So if you’re bored…