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#1 2006-02-27 21:51:50
- ganesh
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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?
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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#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 2x³-x²-3mx-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?
IPBLE: Increasing Performance By Lowering Expectations.
#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 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.
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! 
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 x²-3x+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 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
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: (x²+1/x²) - 3(x-1/x)-2=0
Character is who you are when no one is looking.
#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
#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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#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.
