上うえ三さん角かく行ぎょう列れつ

noun

upper triangular matrix

A square matrix where all entries below the main diagonal are zero. Used in linear algebra.

• 上うえ三さん角かく行ぎょう列れつの行ぎょう列れつ式しきは対たい角かく成せい分ぶんの積せきに等ひとしい。

  The determinant of an upper triangular matrix equals the product of its diagonal entries.