Cogito
Integrated Math 3 · Chapter 2 · Lesson 2
Operations With Rational Expressions
Fractions, with polynomials inside.
12 problems · about 21 minutes · A-APR.D.7
Figure — use these to answer the problems
2/3 is less than 3/4.
Warm Up
Straightforward practice. Get the method working first.
5 problemsFor 1 ÷ (x − 9), which value of x is excluded?
AnswerWhat may be cancelled from a fraction?
- Whole factors only.
- Any matching symbols.
For 1 ÷ (x − 5), which x is excluded?
AnswerFor 1 ÷ (x + 4), which x is excluded?
AnswerCan the x values in (x + 3) ÷ (x + 5) be cancelled? 1 yes, 0 no.
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsTo divide by a fraction, what do you multiply by? 1 the same, 2 the reciprocal.
Answer(x² − 4) ÷ (x − 2) simplifies to x + k. What is k?
Answer(x² − 25) ÷ (x + 5) simplifies to x − k. What is k?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsPut the addition process in order.
Write 1 to 4 in the boxes to put these in order.
- Factor every denominator.
- Build the least common denominator.
- Rewrite each fraction over it.
- Add the numerators and simplify.
(x² − 36) ÷ (x − 6) simplifies to x + k. What is k?
AnswerThe Restriction
For (x − 3) ÷ (x + 2), which value of x is excluded?
AnswerThe Cancel
In (x² − 9) ÷ (x² + 5x + 6), which factor cancels? Enter 3 for (x + 3).
Answer