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2. �ber das Maximum des absoluten Betrages von $$\frac{1}{{b - a}}\int\limits_a^b {f\left( x \right)} g\left( x \right)dx - \frac{1}{{\left( {b - a} \right)^2 }}\int\limits_a^b {f\left( x \right)dx} \int\limits_a^b g \left( x \right)dx$$
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