Linear Algebra Drills
The procedures, until they are fast
MA201 teaches each of these once, against one example, and moves on. This is the volume — thirty-three procedures from a dot product to a condition number, on questions generated fresh that never run out. Each stays green only while your recent answers hold.
- Modules
- 9
- Drills
- 33
- Build steps
- 0
- Time
- ~7h
Walk out able to
Reduce a matrix, read its rank, find both eigenvalues of a $2 \times 2$ and project onto a line — without stopping to rebuild the method first.
What you drill
Vectors and systems
Norms, dot products, spans, elimination, the three verdicts.
Matrices and determinants
Products, inverses, the plane maps, 2×2 and 3×3 by hand.
Spaces, rank, eigenvalues
Independence, coordinates, pivots, subspaces, eigenvalues.
Orthogonality and fitting
Projection, Gram–Schmidt, normal equations, singular values.
What you get
Skills that stick
Every project mixes short lessons, focused drills and real build steps, so you finish with working code and the judgement behind it.
You will practise
- Norms, dot products, spans, elimination
- Matrix products, inverses, determinants
- Rank, the four subspaces, eigenvalues
- Projection, Gram–Schmidt, least squares
Afterwards you can
- Reduce and read a rank off a matrix
- Find both eigenvalues of a 2×2
- Project, and name the residual
- Read a condition number for what it costs
Modules
Step by step
Each module builds on the last. Read a short lesson, drill it until it's second nature, then put it to work.
- 1
Vectors and their lengths
~42 minMeasure, dot and classify a pair of vectors without rebuilding the formula first.
- LessonWhat this project is for4 min
- DrillMeasure a vector three ways8 min
- DrillDot two vectors8 min
- DrillRead the angle off the sign11 min
- DrillName what they span11 min
- 2
Solve and read a system
~47 minEliminate, back-substitute, and call the verdict before solving anything.
- DrillSolve a 2×2 system14 min
- DrillClear the entry under a pivot8 min
- DrillBack-substitute upward14 min
- DrillOne, none, or infinitely many11 min
- 3
Matrices as maps
~41 minApply, compose and invert a 2×2, and recall the map each one performs.
- DrillApply a matrix to a vector8 min
- DrillMultiply two matrices8 min
- DrillName the transformation11 min
- DrillInvert a 2×214 min
- 4
Spaces and independence
~36 minTest a subset, spot a redundant direction, and read coordinates off a basis.
- DrillRun the subspace test11 min
- DrillIndependent, or redundant11 min
- DrillFind the coordinates14 min
- 5
Rank and the four subspaces
~42 minCount pivots, deduce the count you were not given, and place each subspace.
- DrillCount the pivots20 min
- DrillRank plus nullity11 min
- DrillPlace the subspace11 min
- 6
Determinants
~50 minEvaluate at 2×2 and 3×3, and carry a determinant through an operation.
- DrillTake a 2×2 determinant8 min
- DrillTake a 3×3 determinant20 min
- DrillTrack a row operation11 min
- DrillUse a determinant identity11 min
- 7
Eigenvalues and eigenvectors
~50 minVerify, find, move and judge the eigenvalues of a 2×2.
- DrillRead an eigenvalue off a vector14 min
- DrillFind both eigenvalues14 min
- DrillMove the eigenvalue11 min
- DrillWill it diagonalise11 min
- 8
Orthogonality and fitting
~59 minProject, classify, strip an overlap, and form the normal equations.
- DrillProject onto a line14 min
- DrillOrthogonal or orthonormal11 min
- DrillTake one Gram–Schmidt step14 min
- DrillForm the normal equations20 min
- 9
Spectral structure
~39 minClassify a form, size the singular values, and read the conditioning.
- DrillClassify a quadratic form14 min
- DrillFind the singular values14 min
- DrillRead the condition number11 min
More in Algorithms & interviews
Keep going
Discrete Mathematics Drills
MA101 taught it once. This is the volume.
Intermediate~8h8 modules
Interview: Two Pointers & Sliding Window
Read the problem. Then say whether a window applies at all.
Intermediate~3h4 modules
Interview: Trees & Graphs
One skeleton. Then the family it answers.
Intermediate~5h6 modules
Interview: Dynamic Programming
Most problems are not new. Learn to see the shape.
Advanced~5h5 modules
Ready when you are.
Work through it at your own pace and pick up right where you left off.