Given a, b, c∈(0,1) and ab+bc+ac=1, find the minimum value of 1−a1+1−b1+1−c1.
Pick one
Solution
Since 0<a, b, c<1 satisfy the condition ab+bc+ac=1,
it follows that (a+b+c)2⩾3(ab+ac+bc)=3
Therefore, a+b+c⩾3,
Since (1−a1+1−b1+1−c1)(1−a+1−b+1−c)⩾(1+1+1)2
Therefore, 1−a1+1−b1+1−c1⩾3−(a+b+c)9⩾29+33.
The minimum value of 1−a1+1−b1+1−c1 is 29+33 if and only if a=b=c=33.
Therefore, the correct answer is D.
To determine a+b+c⩾3, use the Cauchy-Schwarz inequality (1−a1+1−b1+1−c1)(1−a+1−b+1−c)⩾(1+1+1)2, which allows us to find the minimum value of 1−a1+1−b1+1−c1.
This problem examines the minimum value of 1−a1+1−b1+1−c1 and the application of the Cauchy-Schwarz inequality, making it a medium-level question.
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Source: NuminaMath-1.5,
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