Finding Rate of Change
- Thread starter flakine
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How did you switch from dividing by h (in the first line) to multiplying by h (in the second)? Why do all your denominators suddenly become numerators? According to what you've done, 1/2 + 1/2 equals 4, since 1/2 equals (1)(2) = 2.
Eliz.
Eliz.
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You seem to have it set up correctly. Now a little algebbra. Find and achieve Common Denominators. Ignore the 'h' in te denominator for a moment.flakine said:
2/(a+h) - 2/a = [2/(a+h)]*(a/a) - (2/a)*[(a+h)/(a+h)] = [2*a - 2*(a+h)]/[a*(a+h)]
OK, put the 'h' back in the denominator and see where to go from there.
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I'm really not encouraged. What we have here is some elementary algebraic manipulation. If you SHOULD be in Intermediate/Advanced Algebra, these things SHOULD be known to you. Are you in the right class?
1) You mistreated denominators, magically transforming them into numerators.
2) You didn't seem to know how to add fractions. {Common Denominator}
3) Now, you don't seem to know how to divide fractions. {Reciprocal and Multiply}
4) So far, you have shown extremely little correct work except by copying what others have given you.
In this problem, there is one more step, recognizing the Unity Property of 1 for Multiplication. I have no confidence that you will get through it. I suggest VERY STRONGLY, if you are truly struggling with EVERY STEP of this problem, that you go have a chat with your teacher or seriously consider whether you belong in this course. On the other hand, if you're just trying to get us to do your homework, well, there's not much I can say about that and remain polite. In either case, we really can't help you, here.
So, what's it going to be? One of my choices or a third of your own imagination? Perhaps we can back up to basic algebra and see you there?
1) You mistreated denominators, magically transforming them into numerators.
2) You didn't seem to know how to add fractions. {Common Denominator}
3) Now, you don't seem to know how to divide fractions. {Reciprocal and Multiply}
4) So far, you have shown extremely little correct work except by copying what others have given you.
In this problem, there is one more step, recognizing the Unity Property of 1 for Multiplication. I have no confidence that you will get through it. I suggest VERY STRONGLY, if you are truly struggling with EVERY STEP of this problem, that you go have a chat with your teacher or seriously consider whether you belong in this course. On the other hand, if you're just trying to get us to do your homework, well, there's not much I can say about that and remain polite. In either case, we really can't help you, here.
So, what's it going to be? One of my choices or a third of your own imagination? Perhaps we can back up to basic algebra and see you there?
You know, I'm returning to school after being out a long time. I took the placement test and this is where I ended up. I only wanted a little help but instead I get a bunch of insults. I may be a little rusty, but that's the reason I asked for help. I foolishly believed that was what FreeMathHelp.com was there for.
Anyway I solved the problem.
(-2h/a(a+h))/h
-2h/a(a+h)*1/h
-2h/(ha^2+ah^2)
-2/(a^2+ah)
-2/a(a+h)
So much for your prediction Genius!
Anyway I solved the problem.
(-2h/a(a+h))/h
-2h/a(a+h)*1/h
-2h/(ha^2+ah^2)
-2/(a^2+ah)
-2/a(a+h)
So much for your prediction Genius!
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It really would be beneficial if you would decide not to be insulted where no insult was intended. This list was only factual, not insulting. I did not make a prediction; I expressed only lack of confidence. I certainly am willing to have my confidence increased. Are you willing to be challenged when it seems necessary to one with sufficient judgment?
I certainly can appreciate your position. It can be a very difficult thing to return after a long absence. I have no problem with the concept that initial efforts can be very disappointing. That certainly seems to be what is going on, here. Try to examine what was different between your first effort (8:17 this morning) and the effort just demonstrated. A LOT rusty...a little rusty...needs a bit of work...looks pretty good...you got it. It is not an uncommon sequence. I assume you showed us only a couple fo those steps. You did the rest on your own.
Good work. What's next?
I certainly can appreciate your position. It can be a very difficult thing to return after a long absence. I have no problem with the concept that initial efforts can be very disappointing. That certainly seems to be what is going on, here. Try to examine what was different between your first effort (8:17 this morning) and the effort just demonstrated. A LOT rusty...a little rusty...needs a bit of work...looks pretty good...you got it. It is not an uncommon sequence. I assume you showed us only a couple fo those steps. You did the rest on your own.
Good work. What's next?
