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#76 Re: Help Me ! » Need this question answered a.s.a.p » 2010-10-22 23:27:46
Oh my mistake, it really is d(t) = 5cos(πt / 12)
And i also didn't add 400 after 12 noon. I edited my first post.
Could you do it again please?
#77 Re: Help Me ! » Need this question answered a.s.a.p » 2010-10-22 22:17:15
Yes i agree with you and I shouldn't have postponed it. There's many other exams to do and I need this question. The thing is that it will take a long time to actually understand the steps just for one question which I can try to understand after the exams.
What varies there? I seriously don't know.
#78 Help Me ! » Need this question answered a.s.a.p » 2010-10-22 21:14:13
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The depth of water d metres in a river, at a time t hours after 12 noon, 400. is given by d(t) = 5cos(πt / 12)
[π is pi]
a) sketch the graph of d(t) against t, showing one cycle on the axes, clearly marking in suitable areas
b) state the period and amplitude of depth of water
c) State the highest level of water and the time of day when this occurs
d) State the lowest level of water and time of day when this occurs
e) by solving an appropriate trigonometric equation, find time of day when level of water in river is equal to 2.5 metres
PLEASE DO THIS QUESTION FOR ME, I HAVE TO STUDY FOR OTHER EXAMS AND WON'T HAVE THE TIME TO ACTUALLY FOCUS IN QUESTIONS LIKE THIS, THIS QUESTION WILL BE A LIFE SAVER.. LAST WEEK, PLEASE DO THIS QUESTION FOR ME.
#79 Re: Help Me ! » q correlation coefficient (diagrams from textbook provided) » 2010-09-16 00:16:01
The textbook is 'Maths Quest 11 Standard General Mathematics TI-NSPIRE EDITION'
So there are 15 pieces of data (I'm guessing that is the data points?) you find the median which is the 8'th score which is lovely but how on earth do you know where to exactly put the vertical and horizontal lines? It has different examples and all of them are different. Sometimes it goes on them points sometimes it doesn't. I don't get how it is done...
#80 Help Me ! » q correlation coefficient (diagrams from textbook provided) » 2010-09-15 01:28:08
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The thing I don't understand is how does finding out the median help you drawing in the horizontal and vertical lines. How do you know if it's going to pass through a few of the data points? Like in the example on that website it has a moderate negative correlation and the median is the 8'th score. How did they put the vertical+horizontal line by knowing the median? I see 6 data points in the B quadrant, 5 in the D quadrant, 1 in both A and C. How did they know all this by just the 8'th score? Thanks.
#81 Re: Help Me ! » Need the asymptopes Of these graphs (100% Understandable Pictures) » 2010-08-17 00:32:20
Maths is fun thanks to you guys 
#82 Help Me ! » Need the asymptopes Of these graphs (100% Understandable Pictures) » 2010-08-16 23:18:11
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How do we find the equations of asymptotes of these?
a) 
b) 
c) 
d) 
#83 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-16 22:21:31
Could you please do this for me and show me how to,
√a^3 b^2 .......................√a^-4 b^2
__________.........X.......___________ X √a^3 b^-1
a^2 b^-1 c^-5.................a^3 b^-1
Key: √ = Square root
^ = power of
_____ = Divided by
........ = Just to fill the gaps in
#84 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 23:32:57
Thanks so much for that!
Looks like I don't understand the signs.
How do you express these out like you did with that. Like a ^ 2 was aa... I guess i just need to know how to do that. I'm not having problem with the question itself just the signs.
(2a)^2 ?
8b^2 ?
8a^2 b^3 ?
(2 ^ 1/3) ^ 2 ?
and please simplify this showing the steps like you did for the cancelling:
3√a^3 b^2
Thank you..
#85 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 23:00:20
I don't understand what we have to do next? Cross out things the letters, numbers? Is there like a rule we have to follow or do? like how do we divide a ^ 2 b ^ 3 with ab first?
#86 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 22:44:09
Yes 
And the answer is in the form 2 ^ an+b Just need to know how to do this. I don't know much about the rules or formula.
#87 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 22:32:30
Yes but how did you get that? Or what formula did you use and how did you use the formula?
#88 Re: Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 22:15:28
I'm sorry for the format.
^ = to the power
----------- = divided by
1. Simplify giving your answer with positive index
a^2 b^3
---------
ab
times this
a^2 b^5
----------
a^2 b^2
2.
a^1/4 X a^2/5 X a^-1/10
3.
Write
2^n X 8^n
-------------
2^2n X 16
in the form 2 ^ an + b
#89 Help Me ! » Exponential Functions and Logarithms? » 2010-08-14 22:00:00
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Where's the best site to understand this topic? I need help and can only understand some parts of it.
For example for my homework given by my teacher I must simplify giving the answer with positive index:
a^2 b^3 / ab X a^2 b^5 /a^2 b^2
and another question:
a^1/4 X a^2/5 X a^-1/10
and questions like:
write 2^n X 8^n / 2^2n X 16 in the form 2^an+b
There's lots more like these then to the sketch graphs which want us to give equations of asymptopes and the axes intercepts etc. Transformations..
Any recommended website that teaches you this in detail?
Thanks.