MathDB
system of inequalities

Source: LIMIT 2019 CBS1 P12

April 28, 2021
inequalities

Problem Statement

The system of inequalities ab214a-b^2\ge\frac14bc214b-c^2\ge\frac14cd214c-d^2\ge\frac14da214d-a^2\ge\frac14where a,b,c,da,b,c,d are real numbers has <spanclass=latexbold>(A)</span> no solutions<span class='latex-bold'>(A)</span>~\text{no solutions} <spanclass=latexbold>(B)</span> exactly one solution<span class='latex-bold'>(B)</span>~\text{exactly one solution} <spanclass=latexbold>(C)</span> exactly two solutions<span class='latex-bold'>(C)</span>~\text{exactly two solutions} <spanclass=latexbold>(D)</span> infinitely many solutions<span class='latex-bold'>(D)</span>~\text{infinitely many solutions}