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amania_r
Differentiation question?
Hi. Any tips on how to differentiate:
y = a + bx + sqrt( c + dx^2)
with respect to x. I don't think I can use the chain rule because x is in two different places.
Thanks
3 個解答Mathematics2 年前Outdoor tomato plants - green fruit?
I have a number of outdoor tomato plants. I didn't pick off the runners earlier in the season. I now have lots of foliage and lots of tomatoes but they are mostly green. What can I do now to encourage ripening - e.g. some sort of pruning?
4 個解答Other - Home & Garden8 年前Twinings Blackcurrant and Vanilla tea. How do they get away with it?
Twinings Blackcurrant (big letters) & Vanilla tea. Picture of blackcurrants on the front of the box, description of blackcurrants on the back of the box. Ten (!!) ingredients listed, *none* of them blackcurrant. Confused.
5 個解答Non-Alcoholic Drinks8 年前British film director?
Who's the film director with dark wavy hair and bags under his eyes? (just saw him in the street)
6 個解答Movies9 年前Beginner's bass guitar questions?
I'm looking to buy my 15 year old son a bass guitar. He plays an ordinary electric guitar a little but is new to bass.
Some questions:
Is it better to buy budget new or something better second hand?
Can you recommend any particular manufacturers and models?
Anything else should look out for?
Many thanks
7 個解答Other - Music1 十年前Anyone see the meteor shower last night?
I saw about 15 between 9:30 and 10pm. Didn't fancy getting up at 2am to see the peak.
5 個解答Astronomy & Space1 十年前Topology puzzle question?
Imagine 3 points represent gas, water and electricity suppliers. 3 more points represent houses. Is it possible to link every house to every utility without crossing wires/pipes?
I think not unless it is located on a torus shaped planet.
2 個解答Mathematics1 十年前Python question. Syntax error?
I'm new to Python and I have an example script that has a syntax error, but I can't see what's wrong. Here it is:
class SimpleGraph:
def __init__(self):
self._spo = {}
self._pos = {}
self._osp = {}
def add(self, (sub, pred, obj)):
I get a syntax error on the ( before sub. I'm running Python 3.1. Any ideas?
1 個解答Programming & Design1 十年前Can't run programs on Vista. .exe not recognised?
After what looks like a virus attack, I can no longer run programs on my laptop. When I click on a program (e.g. Internet Exporer) it brings up a window with a list of programs that I might like to open it with. I think the association of the .exe extension with the ability to just run the program has been lost in the registry.
If I run the program from the DOS command prompt, then it works just fine. Do you know how I can restore the registry setting back to the correct setting? (I can run regedt32.exe from the command line)
Thanks
2 個解答Software1 十年前Is a sphere (possibly flattened) the only possible shape for a planet?
Could a torus (dough nut) be formed? Possibly by a stream of debris that loops in a circle due to gravity and then coalesces into the torus. With some spin it might just be stable, any thoughts?
5 個解答Astronomy & Space1 十年前'Green' actions that have the opposite effect...?
I once saw someone washing a milk bottle top under a hot running tap. When questioned, they said they were cleaning it before recycling it. I'm sure the energy used to clean it was far higher than that saved in recycling 0.5g of aluminium.
Also, the line on email footers containing "Please avoid printing this email" (or similar) probably takes 5% of emails onto a new page boundary resulting in more wasted paper.
Do you have any other examples of counterproductive Green actions?
8 個解答Green Living1 十年前MS Publisher 2003 - Problem with navigation menu?
I have a simple website designed using Publisher. For most people, the navigation menu correctly takes the user to the sub-pages. For some users however, they get a blank page when they click on a navigation bar button.
Other information...
One of the users that has problems is running IE 6
Another user said that if they cut and paste the hyperlink URL into the browser they get the sub page.
If it helps, the web site is: www.bathamptonfinearts.org.uk
1 個解答Other - Internet1 十年前Mortgage lump sum pay in - reduce term or reduced payments?
I'd like to pay in a lump sum that is about 20% of my outstanding mortgage (mostly repayment - some endowment type). The Bank has suggested that I can either reduce the term of the mortgage or reduce the monthly repayment. Is there a generally accepted best option?
5 個解答Personal Finance1 十年前Boil beans on a high heat for 10 minutes - why?
On many dried bean packets, the instructions are something like:
soak for 8 hours
boil vigourously for 10 minutes
simmer for 30 minutes
Why the boil vigourously for 10 minutes? The water is the same temperature as if you were to simmer it instead
3 個解答Physics1 十年前Ideas for relevent bible verses on the subject of Outreach?
I'm leading a Bible study on Outreach. Can anyone recommend some suitable Bible verses related to this?
2 個解答Religion & Spirituality1 十年前Eagles kill wolves - how?
While on a visit to China a few weeks ago, I saw part of a TV program about a tribe (Chinese or Mongolian looking) that lived in the mountains. They would hunt on donkeys and have a eagle on their arm. When they spotted a wolf in the distance, they would dispatch the eagle. The eagle would land on the wolf's head and they rolled together on the ground. The next scene was of a dead wolf. Could the eagle have killed the wolf? (sounds unlikely) or maybe they just blinded it making it easy for the hunters to kill?
5 個解答Zoology1 十年前How much water does a bullet have to pass through before it's harmless?
You'd think it would be a few inches, but on films like Saving Private Ryan, it is many feet - confused!
6 個解答Engineering1 十年前New Scientist - Alien SMS competition. Winning entries?
In the 13th Jan edition, they gave the 10 runners up to the competition: what SMS would an alien send home soon after arriving on our planet. No more than 160 characters of course.
These were hilarious. Does anyone know what the winning entries were? (published the week before)
3 個解答Other - Science1 十年前Slow neutrons. Do they collect at the centre of the Earth?
As neutrons are pretty inert and have mass, do slow neutrons collect at the centre of the Earth? If not, where do they end up?
2 個解答Physics1 十年前