All College Algebra Resources
Example Questions
Example Question #3 : Factoring Polynomials
Factor the polynomial
can be looked as . When A=1, as it does in this case, we can ignore it. So now we need to look at factors of "C" that add up to "B."
Factors of 20 are:
1 20
2 10
4 5
Of these three options, the 4 & 5 will add to 9, so we write
Example Question #91 : Review And Other Topics
Factor the polynomial
needs to be seen as . Then we need to ask what factors of "C" will equal "B" if one of them is multiplied by "A"
So first thing is to find factors of "C," luckily 5 only has 2:
1 and 5
We need to write an equation that uses either 5, 1 and a "*2" to equal -9.
Now we can write out our factors knowing that we will be using -5,2,and 1.
(__X+___)(___X+____)
from the work above, we know we have to multiply the 2 and the -5, so they need to be in opposite factors
(2X+__)(X-5)
that only leaves one space for the 1
Example Question #11 : Factoring Polynomials
Factor the polynomial
needs to be seen as . Then you need to ask what factors of "C" will equal "B" when added together.
C=-18, factors of -18 are:
-1,18
-2,9
-3,6
1,-18
2,-9
3,-6
Of those factors, only -3,6 will give us "B", which in this case, is "3"
so
becomes
Example Question #12 : Factoring Polynomials
Factor completely:
Set , and, consequently, . Substitute to form a quadratic polynomial in :
Factor this trinomial by finding two numbers whose product is 8 and whose sum is . Through trial and error, these numbers can be found to be and , so
Substitute back for :
The first binomial is the difference of squares; the second is prime since 8 is not a perfect square. Thus, the final factorization is
Example Question #13 : Factoring Polynomials
Factor completely:
Set , and, consequently, . Substitute to form a quadratic polynomial in :
Factor this trinomial by finding two numbers whose product is 8 and whose sum is . Through trial and error, these numbers can be found to be and , so
Substitute back for :
Both factors are the difference of perfect cubes and can be factored further as such using the appropriate pattern:
Example Question #92 : Review And Other Topics
Factor:
Step 1: Break down into factors...
Step 2: Find two numbers that add or subtract to .
We will choose and .
Step 3: Look at the equation and see which number needs to change sign..
According to the middle term, must be negative.
So, the factors are and .
Step 4: Factor by re-writing the solutions in the form:
So...
Example Question #91 : Review And Other Topics
Rationalize the following fraction:
Rationalize the following fraction:
To rationalize a denominator, we will multiply the top and bottom of the fraction by the denominator.
And we have our answer
Example Question #2 : Rational Expressions
Simplify the following:
First we need to factor both polynomials.
Becomes
Now we cancel out any variables that are in BOTH the numerator and denominator. Remember that if a group of variables/numbers are inside parenthesis, they are considered a single term.
The common term in this case is , removing that from the equation gives us
Example Question #2 : Rational Expressions
Simplify the following
The first step is to factor both polynomials:
Becomes
Now we cancel out any terms that are in both the numerator and denominator. Remember that any variables/numbers that are in parenthesis are considered a single term.
In this case, the common term is
Once we remove that, we are left with:
Example Question #92 : Review And Other Topics
Simplify the following:
The first step is to factor both polynomials
becomes
Now we cancel out any terms that are in both the numerator and denominator. Remember that any variables/numbers that are in parenthesis are considered a single term.
In this case, the common term is
Simplified, the equation is: