If you do the following thing in Maths , a ( b c ) = ( a b ) c then it will be a Big Mistake !!!
But for how many triples of integers ( a , b , c ) such that 0 ≤ a ≤ 1 0 and 0 < b , c ≤ 1 0 , is the above said "False" property seen to be "true" ?
This problem is a part of my set Mistakes Give Rise to Problems .
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oh no i did not consider the 90 triplet case.
I'm trying to guess why it's exactly 1 less that 300....
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LOL that 1 TRIPLE ( 0 , 0 , 0 ) made this happen, it's because 0 0 is not defined.
in 2nd case ie a = 1 , 2 cases occur i) b=0 and c can have 10 values except 0 and ii) when b assumes the other 10 values and can have 11 values so the 2nd case total becomes 120 .Correct me if i am wrong
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b can't be 0 because see what is the given range, there is strict inequality at 0 < b , c ≤ 1 0 . So you can't take b or c to be 0.
Good problem, I missed the 9 triples and got 290
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Lol. I had the answer right in front of my eye, and I didn't count the last 8 triples...
same way! nice problem
I have a question: The 3 restrictions are :
0<=a<=10
0<b
C<=10
Under these conditions "bc" and "b^c" are always real numbers
And 1 to any real power is 1
There are also infinite combos of b and c
So how does your solution assume that b and c both only have 10 possible numbers to choose from?
Please explain what detail I am missing?
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Actually problem is to find solutions of a b c = a b c
We break this in 3 cases, (i) a = 0 , (ii) a = 1 and (iii) a ∈ [ 2 , 1 0 ]
(i) a = 0 , the case is true for all permitted ( b , c ) , giving 1 0 0 triples ( a , b , c )
(ii) a = 1 , the case is true for all permitted ( b , c ) giving 1 0 0 triples ( a , b , c )
(iii) a ∈ [ 2 , 1 0 ] , we have the case b c = b c and this is true if c = 1 , giving 1 0 pairs ( b , c ) and a has 9 choices, gives 9 0 triples ( a , b , c )
If c = 1 , only and only case is b = c = 2 where we get 2 2 = 2 × 2 = 4 again, a has 9 choices, giving 9 triples ( a , b , c )
So as a whole there are 1 0 0 + 1 0 0 + 9 0 + 9 = 2 9 9 triples following needed thing.