【入試数学(基礎)】図形の性質3 正四面体の外接球の半径・内接球の半径

Don't underestimate it. Proving where the center of a sphere is can be tricky. Once you know where the center is, and realize that there is something else, you can find it right away! Click here for teaching materials → https://drive.google.com/file/d/1H8qQ... ------------------------------------ ◆Previous video    • 【入試数学(基礎)】図形の性質2 方べきの定理・接弦定理   ◆48 lessons on essential topics in Mathematics IA    • 【入試数学(基礎)】数と式1 ルートの計算   ◆Official website https://tadayobi.jp/ ◆Subscribe    / @tadayobi-science   ◆Official Twitter   / tadayobi_jp   ------------------------------------ Equipment used: Black Magic Design ATEM Mini Pro https://www.blackmagicdesign.com/jp/p... "Tadayobi" is a completely free online university entrance exam prep school available on YouTube. Mathematics classes are streamed every day from Monday to Sunday at 8pm!