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Category Archives: Rational Expressions

Factoring + Rational Expressions

Posted on April 24, 2013 by mpershan | 1 Reply

IMG_20130331_171842 IMG_20130331_172201

What’s the fastest way of helping these students?

Thanks to Anna for the submissions.

 

Posted in Arithmetic with Polynomials and Rational Expressions, Rational Expressions, Rational Expressions.

Multiplying fractions

Posted on August 31, 2012 by mpershan | 3 Replies

In case you’re having trouble reading the kid’s work, and because the top of the question is cut off, I’m going to reproduce the problem in text below the image:

Question: What is the product of \frac{x^2-1}{x+1} and \frac{x+3}{3x+3} ?

Answer: \frac{3x^2-3}{3x+3}*\frac{x+3}{3x-3}

\frac{3x^2+9}{9x+9} \rightarrow \frac{1x^2+3}{3x+3}

 

The usual: What does he know, what doesn’t he know, and what would you do next?

Posted in Arithmetic with Polynomials and Rational Expressions, Rational Expressions, Uncategorized.

Not-so-simple simplifying

Posted on June 28, 2012 by mpershan | 2 Replies

What’s the student thinking, and how can we help?

Rational_expressions
Posted in Algebra 2, Rational Expressions.

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This site is about compiling, analyzing and discussing the mathematical errors that students make. Every day a new mistake is posted. The site is edited by Michael Pershan, a high school math teacher from NYC.

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