One way to resolve the tension between the formal and informal reasoning is to say that you haven't properly translated Q and R.
These two sentences have equivalent meanings:
1)I have enough money to buy coffee.
2)Possibly, I could buy coffee.
Since they have the same meaning, they...
I have a couple of true and false questions I'm looking at in order to review for my final next Friday (not tomorrow). First, when someone says that a function is continuous does that mean continuous on its domain or continuous at all reals? For example, tan(x) is continuous on its domain but...
I found this proof on a blog I read. Can you find what (if anything) is wrong with it?
Here's a link to the whole post: http://www.analphilosopher.com/posts/1068508260.shtml" [Broken]
Next semester I'm taking Intro to Physics II and Calculus II concurrently. Calc II is a co-requisite for Physics II, but in Physics I I've found that sometimes the teacher presumes knowledge not yet taught in Calc I (co-requisite for physics I). I was wondering if there were any topics in Calc...
Irving M. Copi and Carl Cohen, Intro*duction to Logic is the best to my knowledge. If you're planning to take the class sometime in the future, figure out what text your college uses and just get that. If you're looking for something cheap and easy (you can learn basic skills very quickly)...
I wouldn't trust that dumblaws.com site. For example, it says Tennessee (my homestate) has outlawed interracial marriage. But any idiot with a computer can look up the state constitution and see that that particular section has been repealed.
A pulsar is a rapidly rotating neutron star that emits a radio beam the way a lighthouse emits a light beam. We receive a radio pulse for each rotation of the star. The period T of rotation is found by measuring the time between pulses. The pulsar in the Crab nebula has a period of rotation of...
A 1000kg boat is traveling at 90km/h when its engine is shut off. The magnitude of the frictional force f between the boat and water is proportional to the speed v of the boat: f=70v where v is in meters per second and f is in Newtons. Find the time required for the boat to slow to 45 km/h...
I've only seen predicate logic that has one variable after a general term like Fx, Gy, etc. What does it mean to have several variables after a general term?
I'll take #1. Are you using relations in 2 and 3? I'll admit I never studied those on my own(taking a logic course next semester).
1| (((X&Z)&Y)v(~X>~Y)) [premise]
2| (X>Z) [premise]
3| (Z>Y) [premise]
4|| X...
I'll have to give this one to AKG, although Honestrosewater's proof is correct. It was my impression that RAA proofs start by assuming the opposite of the conclusion. Honestrosewater's assumption is entailed by the negation of the conclusion by using only one inference rule, but since he didn't...
Since this forum seems a little slow, I propose a game. I'll post some sort of logic question (it can be symbolic or some sort of trivia about logic) and the next poster tries to answer. When s/he gets it correct, I'll verify that it was the answer I was looking for and then the poster gets to...
Following the the logical positivist convention of defining a term in use I am seeking a definition of free will as it occurs in the proposition "[agent]A has free will". This will involve formulating an equivalent proposition which uses no synonyms of "free will".
I believe it can be done in...
According to Wikipedia omnipotence is only mentioned in Revelations. Thus the Biblical justification for a belief in omnipotence is very weak.
The same source argues that the conception of God entails something like the perfection of all predicates or all good predicates. Since one of those...
String theorists' contention that there are indivisible strings is comparable to the atomism of Democritus and Leucippus. Shouldn't this be in the homework section?
This question vividly reminds me of Godel's sentence G. Would it be fruitful to apply the same method to omnipotence?
Call the act X 'the act which cannot be performed by God'. God either can or cannot perform this act. If he can't perform act X, then he's not all powerful. If he can then...
Also in the book the author says to find an algebraic definition for the tree, but he doesn't say that it must be formed in the same way as G(n). So for example we could put F(n) above n instead of under it, or call F(n) n and n F(n) instead of the way we started.
Could you explain what this \in symbol means? I'm not familiar with it. My math education is pre-cal and some self-taught Calculus.
For the F(n), you define in your last post, is that the inverse function of X? If so how would you find it?
Thank you for your interest. Here is a .jpg of the G(n) tree. The F(n) numbers are written beside them in pencil.
Notice how G(n) has the Fibonacci sequence running up the right hand side. Thus F(n) has the sequence running up the left hand side.
I'm reading Godel, Escher Bach: An Eternal Golden Braid by Hofstader. He describes a geometric shape formed by writing n in a circle and then writing G(n) in a circle below it and connecting the two circles with a line. It ends up looking sort of like a tree. Try it yourself if you want...
I'm working though Introduction to Logic by Harry Gensler in which he presents his own invention for testing syllogisms-the star method. I was wondering how common this method is in comparison to Venn diagram methods. It's much quicker than Venn diagrams to use, but the beginning student is at a...
Ancient Greek would obviously be for reading original texts, which would be useful in both a philosophy and classics major (two of the several I'm considering). On top of that I'd probably go with German because my course catalogue recommends that people looking into graduate school in the...
I'm a native english speaker who took latin in high school. What language do you think I should learn in college? I'm considering ancient greek because I might go for a classics major, but I'm also thinking about something that would make it easier to travel the world. Other possible majors...
All I wrote was that the change in potential energy was equal to the kinetic energy at some point in the marble's path. Indeed there is no term for the marble's potential energy at the top of the loop because the LHS side of the equation accounts for it. Were I to write the LHS in terms of...
Urban, your 2nd equation will not work because you have neglected the rotational kinetic energy of the marble.
Punchline, use Urban's first equation to determine the minimum velocity that the marble needs at the top of the loop. Then apply conservation of energy to find minimum h. You will...
When the mass it as its maximum displacement what is its velocity? You should know this without having to use a formula. If you don't, review the chapter.
The mechanical energy of a mass-spring system with speed v at position x is E = .5mv^2 + .5kx^2 .
Pick a point in the oscillation and apply this equation. (Hint: there's a special point in its motion which simplifies this problem greatly).
Chronos, while I agree that turbo's explanation doesn't look like anything I've read from what I believe to be credible sources, you aren't helping my understanding at all-the guy turbo was responding to.
Can someone remind me what is causing the redshift? Commonly cited is the "expansion of space" but is this due to the big bang which inflationary cosmology says was caused by negative pressure of the inflaton field? Has this field reached a zero value now or is it still responsible for the...
Thx, math student I understand now. I was used to my pre-cal teacher teacher telling me to find critical points to solve rational inequalties which included numbers not in the domain.
I'm supposed to find all critical numbers of the given function.
Book defines critical number c as the place where f'(c)=0 or where f is not differentiable.
1. g(x)= x + 1/x
2. f(x)= x ln (x)
work:
1. g'(x) = \frac{x^2 - 1}{x^2}
c= 1, -1, 0
Zero is wrong however. I put it in the...
I heard the tsunami affected the period of Earth's rotation? Can someone explain how this happened? My only guess was something to do with conservation of angular momentum.
Anthony Flew, a famous proponent of atheism who recently changed his mind, always delineated between two kinds of atheism. There is the positive atheist who denies the existence of a god and there is the negative atheist who is not a theist because he lacks sufficient reason to believe in a god...
You can solve this with energy.
At any point on the block's path you can find its energy with the equation
E = .5kx^2 + .5mv^2 + mgy
Consider when the spring has been fully compressed to be y=0. Can you do it from there? Note: y does not equal d.
f(f^{-1}(x)) = x
is a composite function . Do you know about these? BTW what math level are you in, what circumstances are you in? It seems like you have an awful lot of questions that could be answered by reading the textbook.
Well as I understand it, we don't have a lot of information about the details about the collision. The balls could have struck each other on the edge instead of through the center of mass. They could also have an electric charge or be irregularly shaped as far as we are concerned. In my book...
Well you have to find the inverse of f(x) first. Then show f(f^{-1}(x)) = x . Can you find an inverse? An inverse g(x) is the graph of f(x) reflected across the line y=x .
For example:
f(x) = 1/x + 5
Defined implicitly the inverse is therefore:
x= 1/y + 5
where
y=...
Hey futb0l,
Are you sure about that? I could be wrong but for the top block ma <_= \mu m g (couldn't figure out less than or equal sign) . So when it isn't slipping kx = 2ma
On the LHS of the equation Nothing gave the angles are given in the problem (east and north). You'll have to solve for the angle (its the same for the x and y direction equations) on the other side.