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#1 2006-02-27 21:51:50

ganesh
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Algebra

A # 1

If x + y + z = 50, xy + yz + xz = 47 and xyz = 60,
what is the value of
(i) x
(ii) y and
(iii) (x+y+z)?


Character is who you are when no one is looking.
 

#2 2006-02-28 00:03:01

krassi_holmz
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Re: Algebra

the numbers are {3,4,5}
12^3=1728


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#3 2006-02-28 00:52:40

ganesh
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Re: Algebra

http://satsuki.ex.osaka-kyoiku.ac.jp/~k022454/good%20job.gif


Character is who you are when no one is looking.
 

#4 2006-02-28 02:11:00

krassi_holmz
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Re: Algebra

Thanks.


IPBLE:  Increasing Performance By Lowering Expectations.
 

#5 2006-03-02 03:20:33

ganesh
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Re: Algebra

A # 2

For waht value of m is 2x-x-3mx-24 divisible by x-2?


Character is who you are when no one is looking.
 

#6 2006-03-02 03:40:22

krassi_holmz
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Re: Algebra

m=2?


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#7 2006-03-02 15:09:19

ganesh
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Re: Algebra

|m|=2 would have been better! The answer is m=-2. Try again, krassi_holmz, probably you made a mistake somewhere.


Character is who you are when no one is looking.
 

#8 2006-03-02 15:11:38

ganesh
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Re: Algebra

A # 3

If ax+bx+x-6 has (x+2) as a factor and leaves a remainder 4 when divided by (x-2), find the values of a and b.


Character is who you are when no one is looking.
 

#9 2006-03-02 19:28:39

ganesh
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Re: Algebra

A # 4

The sum of two natural numbers is 8. Determine the numbers if the sum of their reciprocals is 8/15.


Character is who you are when no one is looking.
 

#10 2006-03-03 03:52:57

mathsyperson
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Re: Algebra

A # 3
From the information given, we can deduce that f(-2) = 0 and f(2) = 4.

-8a + 4b -8 = 0
8a + 4b -4 = 4

Subtract the two equations:
16a -4 = -4
16a = 0
a = 0.

Add the two equations: 8b -12 = 4
8b = 16
b = 2.

f(x) = 2x²+x-6

A # 4
Calling the 2 numbers p and q, we know that p+q = 8, and that 1/p+1/q = 8/15.

Cross-multiplying the second equation gives (p+q)/pq = 8/15. We know that (p+q) = 8, so pq must be 15.

The numbers that add to give 8 and multiply to give 15 are 3 and 5.


Why did the vector cross the road?
It wanted to be normal.
 

#11 2006-03-03 15:26:54

ganesh
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Re: Algebra

Well done, mathsyperson! up


Character is who you are when no one is looking.
 

#12 2006-03-03 16:29:28

ganesh
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Re: Algebra

A # 5

If one of the roots of the equation x-3x+q=0 is twice the other, find the value of q.


Character is who you are when no one is looking.
 

#13 2006-03-07 19:12:43

ganesh
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Re: Algebra

A # 6

If the ratio of the roots of the equation ax-2ax+b=0 is equal to that of ax-2cx+d=0, then which of the following is true?

(a) ab=cd                                      (b) ac=bd

(c) ad=cb                                      (d) db=ca


Character is who you are when no one is looking.
 

#14 2006-03-09 15:15:28

ganesh
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Re: Algebra

A # 7

Solve: (x+1/x) - 3(x-1/x)-2=0


Character is who you are when no one is looking.
 

#15 2006-03-11 19:09:52

amonjezi
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Re: Algebra

y=4
and,y=-1

 

#16 2006-03-11 19:15:51

amonjezi
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Re: Algebra

(x
+1/x^2)-3(x-1/x)-2+2-2=0

 

#17 2006-03-11 19:27:02

amonjezi
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Re: Algebra

(x^2+1/x^2)-3(x-1/x)-2+2-2=0  then (x+1/x)^2-3(x-1/x)-4=0    if (x+1/x)=y  y=4 and -1  now we solves (x+1/x)=4 and (x+1/x)=-1     these equaition very easy

 

#18 2006-03-12 00:17:49

amonjezi
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Re: Algebra

hi ganesh
choice (a) or(c) are true

 

#19 2007-04-24 06:20:02

Eeyore
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Re: Algebra

a7   1 and -1

 

#20 2007-04-24 06:41:04

Eeyore
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Re: Algebra

A#5   q=2

 

#21 2010-10-22 23:12:45

bobbym
Administrator

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Re: Algebra

Hi ganesh;


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.
 

#22 2011-02-13 06:37:00

soroban
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Re: Algebra




. .


.

 

#23 2011-02-13 06:58:53

soroban
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Re: Algebra





.

 

#24 2011-02-14 00:06:44

ganesh
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Re: Algebra

Hi soroban,

I too get the same solutions. Well done!


Character is who you are when no one is looking.
 

#25 2011-03-03 04:54:20

G-man
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Re: Algebra


Maths!......sleep
 

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