0
\\\
x\in(- \frac{\pi}{2} +2\pi n ; \frac{\pi}{2} +2\pi n )
\\\
x \neq \frac{\pi}{2}" alt=" \sqrt{cosx} - \frac{0.3}{cosx}
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\left \{ {{cosx \geq 0} \atop {cosx \neq 0}} \right.
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cosx>0
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x\in(- \frac{\pi}{2} +2\pi n ; \frac{\pi}{2} +2\pi n )
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x \neq \frac{\pi}{2}" align="absmiddle" class="latex-formula">
Ответ: п/2.