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#1 2006-02-26 22:51:50
- Jai Ganesh
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- Registered: 2005-06-28
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Algebra
A # 1
If x² + y² + z² = 50, xy + yz + xz = 47 and xyz = 60,
what is the value of
(i) x
(ii) y and
(iii) (x+y+z)³?
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#2 2006-02-27 01:03:01
- krassi_holmz
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Re: Algebra
the numbers are {3,4,5}
12^3=1728
IPBLE: Increasing Performance By Lowering Expectations.
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#3 2006-02-27 01:52:40
- Jai Ganesh
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Re: Algebra
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#4 2006-02-27 03:11:00
- krassi_holmz
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Re: Algebra
Thanks.
IPBLE: Increasing Performance By Lowering Expectations.
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#5 2006-03-01 04:20:33
- Jai Ganesh
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Re: Algebra
A # 2
For waht value of m is 2x³-x²-3mx-24 divisible by x-2?
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#6 2006-03-01 04:40:22
- krassi_holmz
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Re: Algebra
m=2?
IPBLE: Increasing Performance By Lowering Expectations.
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#7 2006-03-01 16:09:19
- Jai 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.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#8 2006-03-01 16:11:38
- Jai Ganesh
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Re: Algebra
A # 3
If ax³+bx²+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.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#9 2006-03-01 20:28:39
- Jai 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.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#10 2006-03-02 04:52:57
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
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.
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#11 2006-03-02 16:26:54
- Jai Ganesh
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Re: Algebra
Well done, mathsyperson! 
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#12 2006-03-02 17:29:28
- Jai Ganesh
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Re: Algebra
A # 5
If one of the roots of the equation x²-3x+q=0 is twice the other, find the value of q.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#13 2006-03-06 20:12:43
- Jai Ganesh
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Re: Algebra
A # 6
If the ratio of the roots of the equation ax²-2ax+b=0 is equal to that of ax²-2cx+d=0, then which of the following is true?
(a) a²b=c²d (b) a²c=b²d
(c) a²d=c²b (d) d²b=c²a
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#14 2006-03-08 16:15:28
- Jai Ganesh
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Re: Algebra
A # 7
Solve: (x²+1/x²) - 3(x-1/x)-2=0
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#15 2006-03-10 20:09:52
- amonjezi
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- Registered: 2006-03-09
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Re: Algebra
y=4
and,y=-1
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#16 2006-03-10 20:15:51
- amonjezi
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- Registered: 2006-03-09
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Re: Algebra
(x
+1/x^2)-3(x-1/x)-2+2-2=0
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#17 2006-03-10 20:27:02
- amonjezi
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- Registered: 2006-03-09
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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
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#18 2006-03-11 01:17:49
- amonjezi
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Re: Algebra
hi ganesh
choice (a) or(c) are true
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#19 2007-04-23 08:20:02
- Eeyore
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- Registered: 2007-04-16
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Re: Algebra
a7 1 and -1
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#20 2007-04-23 08:41:04
- Eeyore
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- Registered: 2007-04-16
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Re: Algebra
A#5 q=2
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#21 2010-10-22 00:12:45
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Algebra
Hi ganesh;
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#22 2011-02-12 07:37:00
- soroban
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- Registered: 2007-03-09
- Posts: 452
Re: Algebra
. .
.
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#23 2011-02-12 07:58:53
- soroban
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- Registered: 2007-03-09
- Posts: 452
Re: Algebra
.
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#24 2011-02-13 01:06:44
- Jai Ganesh
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- Registered: 2005-06-28
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Re: Algebra
Hi soroban,
I too get the same solutions. Well done!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#25 2011-03-02 05:54:20
- G-man
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- Registered: 2011-02-28
- Posts: 16
Re: Algebra
Maths!......
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