We report on the systems that the Math Information Retrieval group at Masaryk University (MIRMU) prepared for tasks 1 (find answers) and 2 (formula search) of the ARQ Math lab at the CLEF conference. We prototyped three primary MIR systems, proposed several math representations to tackle the lab tasks, and evaluated the proposed systems and representations. We developed a novel algorithm for ensembling information retrieval systems that outperformed all our systems on task 1 and placed ninth out of the 23 competing submissions. Out-of-competition en sembles of all non-baseline primary submissions in the competition made available by the participants placed first on task 1 and third on task 2. Our prototypes will help to understand the challenging problems of answer and formula retrieval in the STEM domain and bring the possibility of accurate math information retrieval one step closer.