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====== Differences ====== This shows you the differences between two versions of the page.

--- gibson:teaching:spring-2016:math445:exam1sample [2016/03/01 12:44]
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+++ gibson:teaching:spring-2016:math445:exam1sample [2016/03/02 12:38] (current)
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@@ Line 8: / Line 8: @@
 **Problem 2:** (slightly tricky) Given a matrix $A$, write one line of Matlab code that convert the $j$th column of $A$ into a row vector and assign it to the variable $x$.
-**Problem 3:** (pretty straightforward) Given a vector $v$, write one or two lines of Matlab code that would return all the odd-numbered elements of $v$.
+**Problem 3:** (pretty straightforward) Given a vector $v$, write one or two lines of Matlab code that would return all the odd-numbered elements of $v$. (By "odd-numbered elements", I mean the elements with odd indices, e.g. $v_1, v_3, \ldots$.)
 **Problem 4:** (moderate) Write Matlab code that defines a function named ''mysin'' that computes $\sin(x)$ using the truncated power series
 \begin{equation*}
-\sin(x) \doteq \sum_{n=0}^{10} -1^{2n+1} \frac{x^{2n+1}}{(2n+1)!}
+\sin(x) \doteq \sum_{n=0}^{10} -1^n \frac{x^{2n+1}}{(2n+1)!}
 \end{equation*}
+**Note: an earlier version of this problem had an error in the Taylor series of** $\sin x$.
 **Problem 5:** (straightforward) Write Matlab code that would solve the system of equations.