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cathgirl

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[quote name='RandomProddy' date='May 25 2004, 09:51 PM'] The logs cancel by putting the whole thing to an exponent of 6.

1 log6(5-3a) = log6(a2-f)


6^(log6(5-3a)) = 6^(log6((a^2)-f)

5-3a = a^2 - f

a^2 +3a - (5+f) = 0 [/quote]
Thank you!! I'm sorry guys the f should be a 5 duh to myself!!

By the way, I have a graphing calculator... ;)

Edited by cathgirl
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Thy Geekdom Come

Well this is humbling...I can't remember this! I got a 32 on the math section of the ACT...but I can't remember this!

ARGH!

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I worked it out and got
a^2+3a-10

I typed it into my quad prgm and got -5 and 2
so (a-5) and (a+2)

Did I do that all right?

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RandomProddy

[quote name='cathgirl' date='May 26 2004, 03:53 AM'] Thank you!! I'm sorry guys the f should be a 5 duh!! [/quote]
In that case it's explicitly solvable:

a^2 +3a - 10 = 0

x^2 + 3x - 10 = 0

a=1, b=3, c=-10

x = (-b [u]+[/u] (b^2 - 4ac)^1/2) / 2a

= -3 [u]+[/u] 7 / 2

= -5 and 2

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[quote name='cathgirl' date='May 25 2004, 10:38 PM'] Well, ONE (grrr... I have a ton) is

1 log6(5-3a) = log6(a2-5)
(the 6's are little and the a is squared..does that make sense, I can't do sub/superscript on posts)

do the log6 cancel each other out? [/quote]
omg i am doing the EAXACT SAME THING!!!!!!!!!!!!!!!

I took the final today :ph34r: :ph34r: :ph34r:

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RandomProddy

[quote name='cathgirl' date='May 26 2004, 03:57 AM'] Did I do that all right? [/quote]
Think so, put it back into the equation to check.

log6(5-3a) = log6(a2-5)

a=-5:

log6(20) = log6(20) yep

a=2:

log6(-1) = log6(-1) yep

first case it's one-to-one, second case it's infinite-to-infinite and periodic so yep

That's correct :)

Edited by RandomProddy
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[quote name='RandomProddy' date='May 25 2004, 10:00 PM'] Think so, put it back into the equation to check. [/quote]
That would be a smart thing to do!! ^_^


By the way...thank you so much!! You are smart!!! (same to you Raphael!!!)

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1337 k4th0l1x0r

[url="http://mcraefamily.com/MathHelp/GeometryTriangleAreaDeterminant.htm"]This site[/url] should help on the triangle area with a matrix calculation.

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#3 (and you thought you were done helping me :P )

3+2i / 5-3i

(we did this so long ago, and I can't find how to do it in my book or my notes)

Do you multiply it by 5+3i or somethin? I have no idea...

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He carries me

hmmm i'm thinkin.... i haven't really done that much with complex numbers

i could go pull out my big ole calc book and see if it has anything in there......

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