Mathematics Articles
by Stan Brown, Oak Road Systems
by Stan Brown, Oak Road Systems
Contents: General | Student Success | Algebra/Precalc | Probability | Trig | Statistics | Calculus
Math Sites and Software (revised Sep 5, 2007)
Help desks, FAQs, Web-based software, and more
TI-83/84 Troubleshooting (revised Oct 4, 2008)
Got a screen full of lines? the “INVALID DIM” message?
Lost a list?
Significant Digits and Rounding (revised Jan 31, 2007)
How to Succeed in Math (revised Sep 25, 2008)
Why is Math so Hard? (revised Jan 25, 2003)
How to Work a Math Problem (revised Sep 25, 2008)
Show Your Work! (revised Aug 19, 2005)
How to Study Math (revised Aug 15, 2006)
How to Take a Math Test (revised Jun 30, 2005)
How to Read a Math Book (revised Dec 18, 2004)
Math Students’ FAQ (revised Mar 5, 2003)
How to Convert Units of Measurement (revised Jul 8, 2004)
Combining Operations (Distributive Laws) (revised Apr 20, 2004)
Solving Polynomial Equations (revised Sep 12, 2008)
It’s the Law — the Laws of Exponents (revised Feb 13, 2006)
It’s the Law Too — the Laws of Logarithms (revised Nov 13, 2008)
Loan or Investment Formulas (revised Sep 30, 2007)
Quadratic Equations on the TI-83/84 (revised Aug 5, 2007)
with TI-83/84 program QUADRAT for download
Evaluating Functions with the TI-83/84 (revised Aug 5, 2007)
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Graphing Functions on the TI-83/84 (revised Aug 5, 2007)
It’s easy to do, harder to do well.
Graphing Piecewise Functions on the TI-83/84 (revised Oct 4, 2008)
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Drawing Inverse Functions on the TI-83/84 (revised Aug 5, 2007)
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Complex Numbers on the TI-83/84 (revised Aug 4, 2007)
or on the TI-89
computations in polar form or rectangular form (a+bi)
Adding Vectors Graphically on the TI-83/84 (revised Aug 7, 2007)
with TI-83/84 program VECADD for download
Multiplying Vectors on the TI-83/84 (revised Sep 18, 2008)
with TI-83/84 program VECPRODS for download
to compute scalar product (dot product) and vector product (cross product)
Probability Histograms on the TI-83/84 (revised Jun 19, 2008)
making a histogram from a discrete probability distribution
Probability of Shared Birthdays (revised May 25, 2003)
In a group of N people, how likely is it that two or more share a birthday?
How big a group do you need before it’s more likely than not?
Medical False Positives and False Negatives (revised Jan 12, 2004)
Binomial Probability Distribution on the TI-83/84 (revised Oct 14, 2008)
or on the TI-89
with TI-83/84 program BINOMPRB for download
Histogram of a Binomial PD on the TI-83/84 (revised Jun 19, 2008)
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Trig without Tears (revised Jun 4, 2008)
You don’t need to memorize those identities!
(also available in a printer-friendly
version)
10-Minute Trig (revised Mar 28, 2006)
for those who just want a fast review
Solving Trigonometric Equations (revised Feb 7, 2006)
Descriptive Statistics of a Data Set on the TI-83/84 (revised Oct 5, 2008)
mean, median, standard deviation, five-number summary, and more
Skewness and Kurtosis on the TI-83/84 (revised Jun 7, 2008)
with TI-83/84 program SKURT for download
Plotting Time Series on the TI-83/84 (revised Sep 15, 2007)
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Frequency Histograms and Polygons the Easy Way on the TI-83/84 (revised Nov 4, 2008)
with TI-83/84 program HISTNPGN for download
Normality Check on the TI-83/84 or TI-89 (revised Jun 23, 2008)
with TI-83/84 program NORMCHEK for download
to determine whether a set of measurements probably comes from a
normal distribution
Least Squares, Down and Dirty (revised Aug 9, 2007)
what we mean by the “line of best fit”, and how we find
it — surprisingly, no calculus is required
Scatter Plot, Correlation, and Regression on the TI-83/84 (revised Sep 20, 2008)
or on the TI-89
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Decision Points for Correlation Coefficient (revised Sep 23, 2007)
Getting ŷ from Any x in a Regression on the TI-83/84/89 (revised Aug 7, 2007)
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Normal Calculations on the TI-83/84 or TI-89 (revised Mar 25, 2008)
in a normal distribution, finding probability or inverse probability
Triage: Which Inferential Stats Case Should I Use? (revised Apr 26, 2008)
Inferential Statistics Cases (revised Sep 9, 2008)
a summary of inferential statistics from a first course in stats
How Big a Sample Do I Need? (revised Nov 11, 2008)
Top 10 Mistakes of Hypothesis Tests (revised Jul 4, 2008)
Critical t on the TI-83/84/89 (revised Jan 27, 2008)
finding critical values for the Student’s t distribution
Inferences about One Population Standard Deviation (revised Aug 10, 2008)
Inferences about One-Pop. Standard Deviation on the TI-83/84 (revised Aug 10, 2008)
with TI-83/84 program SDINFER for download
Computing Critical χ² on the TI-83/84/89 (revised Oct 22, 2008)
with TI-83/84 program INVCHI2 for download
List Operations for Paired t Test on the TI-83/84 (revised Oct 28, 2007)
the calculator’s list operations make this a snap
Confidence Intervals for Two Populations (revised Jul 17, 2008)
estimating the mean difference for paired data, the difference in means for unpaired data, and the difference in proportions for binomial data
Case Study: Gardasil Vaccine (revised Oct 28, 2007)
Inferences about Linear Correlation (revised Apr 4, 2008) explains how to tell whether there is correlation in the population, and how strong it is
Inferences about Linear Correlation on the TI-83/84/89 (revised May 31, 2008)
with TI-83/84 program CORINFER for download
Inferences about Linear Regression (revised Apr 4, 2008) to do hypothesis tests and confidence intervals on slope of the regression line and on y responses to particular x values
Inferences about Linear Regression on the TI-83/84 (revised Apr 4, 2008)
with TI-83/84 program REGINFER for download
Testing Goodness of Fit on the TI-83/84 (revised Jun 1, 2008)
or on the TI-89
with TI-83/84 program GOF for download
The Derivative and the Tangent Line (revised Jun 8, 2005)
one of the big two problems of calculus
Derivatives on the TI-83/84 (revised Apr 29, 2006)
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Optimization (revised Jun 8, 2005)
maximum profit, minimum cost, and so forth
Newton’s Method on the TI-83/84 or TI-89 (revised Jun 22, 2008)
with TI-83/84 program NEWTON for download
to find solutions of an equation numerically
Area by Upper and Lower Sums (revised Jan 12, 2004)
introduction to integration
Definite Integrals on the TI-83/84 (revised Jul 20, 2003)
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u-Substitution — Changing Variables in Integrals (revised Jan 12, 2004)
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