Questions tagged [integral-inequality]

For questions inequalities which involves integrals, like Cauchy-Bunyakovsky-Schwarz or Hölder's inequality. To be used with (inequality) tag.

1106 questions
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Inequality and integrals

I want to prove that: $$\int_0^1\frac{2\sin{x}}{x^2+1}\text{d}x\le\ln{2}$$ So I did the followings: $$\int_0^1\frac{2\sin{x}}{x^2+1}\text{ d}x\le\ln{2}\iff\int_0^1\frac{2\sin{x}}{x^2+1}\text{ d}x\le\int_0^1\ln{2}\text{…
Leos Kotrop
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How prove this integral inequality $\int_{0}^{1}x \sqrt{1+\{f'(x)\}^2}dx\le\ \frac{1}{\sqrt{2}}$

Let $f$ is two differentiable function on $[0,1]$ such that $f(0)=1$, $f(1)=0$, $f'(x)\le 0$, $f''(x)\ge0$ Show that $$\int_{0}^{1}x \sqrt{1+\{f'(x)\}^2}dx\le\ \frac{1}{\sqrt{2}}$$ How do have it? Thank you.
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Prove inequality of natural x, y, z

Prove that, for every x , y, z of the natural inequality is true: $x\ $ $+$ $y\ $ $+$ $z\ $ $\ge$ $3$ $and$ $x$*$y$*$z$ $=$ $1$ I tried to divide by 3, but does not go :(
JWa
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Inequality involving the definite integrals of cos(x) f(x) and sin(x) f(x)

Considering this trivial definite integrals inequality: $$ \mbox{with} \;a \in (0, 2\pi)\; \mbox{such that} \;\; \int_{0} ^{a} \cos(x) dx \; = \; 0 \; \; \; \;\Longrightarrow \; \; \; \; \int_{0} ^{a} \sin(x) dx \; \neq \; 0 $$ Inserting now a…
Luca
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