Stuck on a Maths

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neel_basu
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Stuck on a Maths

Post by neel_basu »

While i was Programming My Brother Got stuck into a problem of Mathematics
I also can't solve it
would anybody please solve it
----------------------------------------
Here is the problem
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If x=cy+bz, y=az+cx, z=bx+ay
Then show that
x²/(1-a²) + y²/(1-b²) = z² / (1-c²)
----------------------------------------
Would anybody Please solve It

Thanks
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feyd
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Post by feyd »

I think we're missing the starting equation.
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neel_basu
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Post by neel_basu »

No no Its the Question Nothing Is Missing
Nothing Else Is Given
I am reapiting It

Code: Select all

If x=cy+bz, y=az+cx, z=bx+ay 
Then show that 
x²/(1-a²) + y²/(1-b²) = z² / (1-c²)
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feyd
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Post by feyd »

There has to be more information, whether you realize it or not. Like what is the purpose of the section in the book you are looking at, what level of math is expected, etc etc. This obviously came from a Math book. Without context it's really annoying to try and solve it for you.
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neel_basu
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Post by neel_basu »

Ya Its A Problem From Math Book's Excersise Of 10th Standerd
Its In a Sample Test Paper In That Book
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feyd
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Post by feyd »

10th standard doesn't mean much to me. More information please.
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neel_basu
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Post by neel_basu »

I Mean He Reads In Class 10
And The Book Is Of Class 10
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feyd
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Post by feyd »

"Class 10" means just as much as "10th standard" here.. just above nothing. Is this Elemental Algebra, College Algebra, Linear Algebra.. actual subject matter is more important then what level of school its for.
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neel_basu
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Post by neel_basu »

I Don't Know Which Family Does This problem belongs to
its in a sample test paper (Question Paper)
IN The Test paper Its Not Written This Problem Is From Which Chapter
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RobertGonzalez
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Post by RobertGonzalez »

You need to substitute to show equality.

Code: Select all

If x=cy+bz, y=az+cx, z=bx+ay 
Then show that 
x²/(1-a²) + y²/(1-b²) = z² / (1-c²)
Would yield:

Code: Select all

(vy+bz)²/(1-a²) + (ax+cx)²/(1-b²) = (bx+ay)² / (1-c²)
Now extrapolate the squares, handle the algebra and check to make sure that both side are equal.
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neel_basu
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Post by neel_basu »

Sorry
Just Now I Looked At the erratta of his book
And I found that this question was wrong
the correct one would be

Code: Select all

If x=cy+bz, y=az+cx, z=bx+ay 
Then show that 
x²/(1-a²) = y²/(1-b²) = z² / (1-c²)
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RobertGonzalez
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Post by RobertGonzalez »

Same thing applies, you are still going to need to substitute and evaulate.
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neel_basu
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Post by neel_basu »

:(
That is
its A Labourous Problem ??
I was Thinking That there is a Shortcut to do it in 2 mins cause only 3.5 marks are given for it.
Thats Why I was not Trying it in that way.
I was thinking there must be a trick some where in it
shwanky
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Post by shwanky »

Algebra is the only trick :-/. I had a professor who would give this crazy proofs on tests worth 15-20% of our class grade. He only taught us algebra and how it applies to trig and calculs... I hate algebra :(
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neel_basu
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Post by neel_basu »

shwanky wrote:Algebra is the only trick :-/. I had a professor who would give this crazy proofs on tests worth 15-20% of our class grade. He only taught us algebra and how it applies to trig and calculs... I hate algebra :(
I dont think algebra is so bad to hate
I Liked Algebra (Speciely Sequence And series) And I also liked Calcullas (Specially Indefinite Integral very much) and Electro magnetism in physics very much
When I was in 10+2.
But I don't like lobourous maths I like the tricky problems.
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