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02.14.2019: One Lesson of Math - Adding and Subtracting Rational Expressions With Binomial and Trino


Today's soundtrack is Scars on Broadway, an album that I really enjoy musically and vocally, but I find its lyrical themes a bit repetitive. I'd like to sit down sometime and tally how many times throughout the album the words "f*ck," "dead," and "Jesus Christ" are repeated.


I've just finished learning how to add and subtract rational expressions with monomial denominators; now I'll be learning to do the same with rational expressions that have binomial or trinomial denominators.


Let's learn how to do it!

 

How to Add or Subtract Rational Expressions with Binomial and/or Trinomial Denominators

  1. Find the non-permissible values of each denominator

  2. Find a common denominator for all expressions

  3. Factor each denominator

  4. Calculate "the product of the different factors with the greatest exponent of each factor" (Pearson's Pre-Calculus 11, p. 562)

  5. Give each expression the same common denominator

  6. Divide the original denominator by the common denominator

  7. Multiply both the numerator and denominator by the quotient found in step 3.1

  8. Consolidate the numerators from each expression above the single common denominator

  9. Keep each numerator in its own set of brackets

  10. For any expression that originally was being added, keep it positive

  11. For any expression that was being subtracted, note it as negative

  12. Simplify and factor as far as possible

  13. Write down the solution and the non-permissible value(s)

 

Okay, seems straightforward enough. Next time, I'll start work on the assignment portion of the lesson!

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