Given three numbers such that 0 < a < b < c < 1 , define
A = a a b b c c , B = a a b c c b , C = a b b c c a .
How do the values of A , B , C compare to each other?
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Consider the ratio B A , which will exceed one if A > B . Reducing the fraction, we find B A = b c c b b b c c = b b − c c c − b = ( b c ) c − b . But c > b , so b c > 1 . Since the exponent c − b is positive, we know B A = ( b c ) c − b > 1 , and A > B . Likewise, the ratio C B yields C B = ( a c ) b − a > 1 , so B > C .
Just assume any three value of a,b,c such as 0.1,0.2 and 0.3. Now use calculator. You get A>B>C or C<B<A.
Wrong answer
A is the biggest because it contains the biggest possible power when using only a, b or c of c^c.
C 'wastes' base c, a big base on a, a small power, and wastes b as power on a as base. But B has a^a to stop this. So C is smaller than b.
The easiest method is to choose any real numbers on the interval. So, WLOG we can define a, b, and c to be rational.
Hence, let a=(1/8), b=(1/4), c=(1/2)
==> A = 1/(2^(1/8))^11
B = 1/(2^(1/8))^13
C = 1/(2^(1/8))^15
Taking ratios:
1) A/B = 2^(1/4)
2) A/C = 2^(1/2)
3) B/C = 2^(1/4)
We know that x^(1/2)>x^(1/4) for x > 1 .
Hence, 2^(1/2)>2^(1/4)
Also, x^(1/2) and x^(1/4) are > 1 for x >1
So, 2^(1/2)>2^(1/4)>1
==> A > C; A>B; B>C
Hence, A>B>C ==> C<B<A
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Let's first compare A and B . Let's first assume A > B . This means a a b b c c > a a b c c b . This simplifies to c c − b > b c − b , which is clearly true. Therefore A > B .
Now let's compare B with C . Again, assume that B > C . This means that a a b c c b > a b b c c a . This simplifies to c b − a > a b − a , which is true. Therefore B > C .
Thus, the answer is A > B > C , or C < B < A .