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gibson:teaching:fall-2016:math753:exam1topics

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gibson:teaching:fall-2016:math753:exam1topics [2016/10/10 09:08]
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gibson [Solving systems of equations]
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 ==== Solving nonlinear equations ==== ==== Solving nonlinear equations ====
  
-Understand +We studied two methods for finding roots of the 1d equation $f(x) = 0$. 
-  * the bisection algorithm + 
-  * the Newton ​algorithm +Bisection algorithm: understand 
-  * the convergence ​rates of bisection ​and Newton ​algorithms+  * how it works 
 +  * what it requires, in terms of the function $f(x)$ and the starting conditions for the iteration 
 +  * the linear convergence rate 
 + 
 +Newton ​method: understand 
 +  * how it works, mathematically and geometrically 
 +  * what it requires, in terms of the function $f(x)$ and the starting conditions for the iteration 
 +  * the quadratic ​convergence ​rate and the assumptions necessary to get quadratic converegence 
 + 
 +You should be able to write pseudo code or Julia code for either method. You're not expected to get the Julia syntax perfectly.  
 + 
 +==== Solving systems ​of equations ==== 
 + 
 +We've studied two methods for solving systems of equations $Ax=b$. 
 + 
 +LU decomposition:​ understand 
 +  * how LU decomposition works 
 +  * the formulae for the multipliers $\ell_{ij}$,​ why the formulae are what they are 
 +  * the backsubstition ​and forward substitution ​algorithms ​(formulae and where they came from) 
 +  * how you piece together LU decomp, forward substitution,​ and backward substitution to solve $Ax=b$ 
 + 
 +QR decomposition 
 +  * how the Gram-Schimidt algorithm computes a QR factorization 
 +  * the formulae for $q_j$, $r_{ij}$, and $r_{jj}$, and where the formulae came from 
 +  * how to use a QR decomp to solve an $m \times m$ (square) $Ax=b$ problem 
 +  * how to use a QR decomp to solve an $m \times n$ (oblong) least-squares $Ax=b$ problem 
 + 
 +In addition we covered some basic linear algebra theory, including 
 +  * transposes 
 +  * inner product 
 +  * the 2-norm, for both vectors and matrices 
 +  * orthogonal matrices 
 +  * how the inner product and 2-norm of both vectors and matrices are preserved under orthogonal transformation 
 + 
 +About formulae: Rather than memorizing them, focus on understanding their meaning and being able  
 +to derive them or the first few instances of a general formula. You should be able to write  
 +pseudocode or Julia code (again, not necessarily perfect syntax) to implement a given formula.
  
-==== Solving systems of linear equations ==== 
  
  
gibson/teaching/fall-2016/math753/exam1topics.1476115712.txt.gz · Last modified: 2016/10/10 09:08 by gibson