3000 Solved Problems In Linear Algebra By Seymour Extra Quality New! Page

The vectors are crisp. You set up the matrix: $$\beginbmatrix 1 & 2 & 1 \ 2 & 1 & -1 \ 1 & 0 & 2 \endbmatrix$$ Wait—the book actually writes the vectors as columns . The solution explains: "Form a matrix with the vectors as columns and reduce to echelon form." You follow the row operations: $R_2 \leftarrow R_2 - 2R_1$, $R_3 \leftarrow R_3 - R_1$. Because the typeface is bold and the spacing is clean, you don't lose your place.

Each section starts with and gradually moves to complex theoretical proofs . The vectors are crisp

The text is smudged. You misread "(1,-1,2)" as "(1,1,2)". You set up the wrong matrix. You get the wrong rank. You give up. 2)" as "(1