Consider the following equation 1 + 2 + 2 ( 2 + 2 ) = d − e + f a + b + c where a , b , c , d , e , f are integers. Calculate a × b × c × d × e × f .
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Is there a specific identity for that, ( 2 − 2 ) = ( 2 − 2 + 2 ) ( 2 + 2 + 2 ) . Such as a − a =
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Oh, nothing remarkable or unique or beautiful. For example, if b = a ( a − 1 ) and c = a , then you'll get a − a
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Please explain how.
For example ....,then you'll get ?????
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@Niranjan Khanderia – Example:
( 1 1 + 1 1 0 + 1 1 ) ( 1 1 − 1 1 0 + 1 1 =
1 1 − 1 1
An unremarkable example, except that this is true in both decimal and binary. Just a quirk example.
this problem has more than one answer !!!! Check a=17 , b=208 , c =6272 , d=7 and if √(e+ √f)=32 ( you can put e=0, f=32 or e=27 , f=25 or f=1 , e=31 and ....) it will satisfy the equation. yet the answer is not 64 . the number of solutions are not infinite but it has more than one solution. inform me if i am wrong pls ????
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Amirhousein Yousefi, you are absolutely right. There are more than one possible answer to this problem, and a=17, b=208, c=6772, d=7, e=27, f=25 is one of them, and the product is decidedly not 64. I'd like to reword this problem, but I'm not the problem creator.
Speechless.
a = 7 , b = 32, c=0, d= 3, e= 1, f=1 seems to work. Hence the product abdcef = 0
a = 7 , b = 32, c=0, d= 3, e= 4, f=0 seems to work. Hence the product abdcef = 0
Can you please explain how you get step four from step three !! How to find square root of three terms under square root sign?
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It's much easier to see how this works if you worked from the bottom up, i.e., start at the last line, and then start multiplying things out. Factoring radicals is always a tricky process. There are techniques but no simple standard procedure.
The author has corrected the typo. So comment removed.
Same method!
@Michael Mendrin please explain me the steps from the 1 in the denominator to 2-2^1/2
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It would have been easier to follow had I put down
2 2 ( 7 + 4 2 + 4 2 + 2 + 2 2 ( 2 + 2 ) ) =
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First, note that
( 1 + 2 + 2 ( 2 + 2 ) ) 2 =
7 + 4 2 + 4 2 + 2 + 2 2 ( 2 + 2 )
The right side is then
1 7 + 4 2 + 4 2 + 2 + 2 2 ( 2 + 2 ) =
( 2 − 2 ) ( 2 + 2 ) ( 6 + 2 + 4 2 + 2 ) ( 2 + 2 ) =
( 2 − 2 ) ( 6 + 2 + 4 2 + 2 ) =
( 2 − 2 + 2 ) ( 2 + 2 + 2 ) ( 2 + 2 + 2 ) ( 2 + 2 + 2 ) =
2 − 2 + 2 2 + 2 + 2
And so
a = b = c = d = e = f = 2
and the answer is 6 4 .