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SU-CS154 Week 8

Last edited: August 8, 2025

NP-Complete, Cook-Levin Theorem, and coNP

owo a chart!

Properties of NP Completeness

for \(NP\) complete \(A\), \(B\), is \(A\ \text{op}\ B\) np complete?

^VRneg.*
nny?nn

Properties of P and NP

for \(P\) or \(NP\) \(A\), \(B\), is \(A\ \text{op}\ B\) np complete?

Time^VRneg.*
Pyyyyyy
NPyyy?yy

SU-CS199 JAN242025

Last edited: August 8, 2025

Key Sequence

Notation

New Concepts

Important Results / Claims

Questions

Interesting Factoids

SU-CS205L FEB042025

Last edited: August 8, 2025

“regularization”: removing columns (i.e. explicitly making things roughly degenerate to fit more generally)

“tall full-rank matrix” (i.e. let \(A\) be \(m \times n\), such that \(m \geq n\)).

Solving such full-rank linear systems—

\begin{equation} Ac = b \implies U \Sigma V^{T} c = b \implies \Sigma \qty(V^{T}c) = U^{T} b \end{equation}

We can now solve this above by simply dividing by the nonzero singular values of each row (since we are full rank, this is true). The last equations are zero.

SU-CS205L FEB132025

Last edited: August 8, 2025