You just need to take look at the graph. If you know what f'(x) (i.e. f prime of x ) it should make sense.
We can see clearly at [4, 6], f'(x) = -3.
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Can I get some help with questions? (1 Viewer)
- Thread starter jssicachoi
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We can see clearly at [4, 6], f'(x) = -3.
The Trial solution is over-complicating a pretty straight-forward problem testing if you understand the concept of definite integrals as signed areas.
Let
be the area between 
and 
and the 
-axis and )
. This area is a 2 unit by 3 unit rectangle, so its area is 6 square units.
\ dx = A_1 - A_2 - A_3 = 4 - 4 - 6 = -6)
\ dx = \bigg[f(x)\bigg]_0^6 = f(6) - f(0))
We are told that = 0)
and so:
 - 0 = -6 \qquad \implies \qquad f(6) = -6)
Let
We are told that
yanujw
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Yeah, I too have to admit that the TEX code on this forum is awkward for those who aren't that familiar with it. I just use the TEX/Equation feature in Microsoft Word half of the time, looks the same to the average user.
@B1andB2 and @username_2, would you please explain what is humorous about my posts here?
Addressing all who have posted here at BoS and readers...
I'm quite serious that I don't want to be a cause of participants feeling discouraged from contributing here. My intention is to be helpful, but if contributing as I do is not having that effect then I need to reflect / re-evaluate.
Addressing all who have posted here at BoS and readers...
I'm quite serious that I don't want to be a cause of participants feeling discouraged from contributing here. My intention is to be helpful, but if contributing as I do is not having that effect then I need to reflect / re-evaluate.
yanujw
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Your contributions are definitely appreciated and valuable. I definitely don't see it as a competition, just making humour of the situation lol.
username_2
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ye didn't mean to annoy you. Just found it funny that you're s0 good at helping that you have had to think about "maybe im doing too much". That I found funny but I respect too. You certainly aren't stopping people as well so yeah.
(although i didnt expect to be called out like this lol)@B1andB2 and @username_2, I was asking not call you out, but because I genuinely don't understand. It's one of the problems with written communication, the clues about intent and emotion, etc, conveyed by facial expressions, tone, etc, are missing. I posted an answer to one thread that @Hivaclibtibcharkwa posted and found that @DrDawn had posted an answer above (now deleted) in this thread. I added a thumbs-up like. Soon after, I saw further posts and references to being ninja'd - an expression, I admit, that I had to look up, being about 95,000 years older than the average poster here. I get the humour here, including the irony that @yanujw's solution was posted about three-quarters of an hour after DrDawn's, though yanujw likely didn't know that as DrDawn deleted the solution 20 minutes after posting it.
My surprise, though, and concern arose from the idea that my posting might discourage others. I was confused that my first post received a "Haha" like, and even more so when what I saw as a clarification was received the same way. I didn't (and don't) imagine that B1andB2 or username_2 were being mean or nasty or anything like that, nor did I felt annoyed. I felt concerned and confused, so I asked. In another example of the miscommunication issues that can occur with text, my intent did not come across. Sad, but such things happen.
Everyone enjoys feeling recognised and appreciated now and then, and no one wants to feel that positive intentions are manifesting as unhelpful contributions. I'm all for mutual support between contributors here, students helping each other to understand and develop their skills, and I can offer alternative approaches and simplifications as well as more detailed explanations where they are useful... I shouldn't be interfering with the peer support that is available as you collaborate together.
My surprise, though, and concern arose from the idea that my posting might discourage others. I was confused that my first post received a "Haha" like, and even more so when what I saw as a clarification was received the same way. I didn't (and don't) imagine that B1andB2 or username_2 were being mean or nasty or anything like that, nor did I felt annoyed. I felt concerned and confused, so I asked. In another example of the miscommunication issues that can occur with text, my intent did not come across. Sad, but such things happen.
Everyone enjoys feeling recognised and appreciated now and then, and no one wants to feel that positive intentions are manifesting as unhelpful contributions. I'm all for mutual support between contributors here, students helping each other to understand and develop their skills, and I can offer alternative approaches and simplifications as well as more detailed explanations where they are useful... I shouldn't be interfering with the peer support that is available as you collaborate together.
@CM_Tutor, your comments are 100% valid. I believe that every user who has seen and/or benefited from your contributions (whether directly or indirectly) can agree that they are highly valuable. I will also reiterate my own opinion that your contributions are pivotal and that the BoS community is lucky to have an individual with an impressive academic background and whose high-quality contributions are considered integral, such as yourself.
I think there is a tendency for mathematics-related threads to be rather "competitive" in nature, implying that students who know the answer to a question on a particular thread may try to post their working/solutions as fast as possible. From what I have observed, I don't think any student is being discouraged from contributing, so this notion of "competition" does not go beyond attempting to be the first student to answer (i.e. positive/healthy/friendly competition). In many cases, multiple answers are provided to a single question and (where applicable) alternative approaches are also provided and explained, many of which you have contributed.
Your contributions are undoubtedly appreciated
I think there is a tendency for mathematics-related threads to be rather "competitive" in nature, implying that students who know the answer to a question on a particular thread may try to post their working/solutions as fast as possible. From what I have observed, I don't think any student is being discouraged from contributing, so this notion of "competition" does not go beyond attempting to be the first student to answer (i.e. positive/healthy/friendly competition). In many cases, multiple answers are provided to a single question and (where applicable) alternative approaches are also provided and explained, many of which you have contributed.
Your contributions are undoubtedly appreciated
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@jimmysmith560, it's desirable to not be too competitive... after all, your reaction score is more than double mine, from fewer posts, and so one could infer that you are valued at close to triple the rate that I am!
laterz laterz
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this got serious real quick lol
I can restore it for you if you like
laterz laterz
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ExtremelyBoredUser
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I think it's more harmful than good if someone was to post an incorrect solution with flaws, imagine if that person felt confident with an incorrect solution and if they replicated it in an exam or somewhere else, they would be in a bad position so having some individual in the community who is mostly, if not, always correct post solutions gives that extra reassurance. It also helps for people posting solutions to get confirmation whether their method is valid/not and seeing someone else's way of doing it helps broaden their thinking.I certainly don't want to be a discouragement to anyone to contribute.
Also, sir, I don't believe you are a discouragement to anyone for contributing - if not you only inspire because some of your solutions have been out of the box and better formatted/communicated which is not only helpful to that one person who's stuck on a problem but also provides people who might have already been confident with the topic to get a better insight. Please don't stop contributing, I think you're solutions are extremely valuable to everyone here whether they're looking for answers or not.
It is DrDawn not Drdraw, hence your difficulty in tagging...
Don't feel bad, DrDawn, and it hasn't caused conflict. I just saw some irony in @A1La5 commenting on being ninja'd by @yanujw when it was actually @DrDawn who answered first, but that original answer had been removed.
On deleting of posts, may I echo @jimmysmith560 in saying that you can delete your own posts but that it is preferable only to do so for a good reason, as they can be of use to others. The same goes to deleting threads... that a thread has served its purpose for the OP doesn't mean it can't be useful to others. This is a very general comment to everyone, not meant to address any single poster.