SOLUTION: How do I solve the equation: 2u^4-5u^3-12u^2+2u-8 divided by u-4 ?

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Question 31461: How do I solve the equation: 2u^4-5u^3-12u^2+2u-8 divided by u-4 ?
Answer by Cintchr(481) About Me  (Show Source):
You can put this solution on YOUR website!
+%282u%5E4-5u%5E3-12u%5E2%2B2u-8%29%2F%28u-4%29+
When dividing by a binomial you MUST make sure that the numerator is in decending order, and that there are no missing exponential values.
This numerator meets that criteria.
Now ... I have not found a way to show the long division in the rendering page so this may seem really long, but bear with me and we will take it all step by step.
FIRST: look at the denominator. you are going to divide by u first. Ask yourself: what number times u equals 2u^4? The answer: 2u^3
NEXT: multiply that value times the denominator
+highlight%282u%5E3%29+%28u-4%29+=+2u%5E4-8u%5E3+ Subtract this value from the numerator ...
+%282u%5E4-5u%5E3-12u%5E2%2B2u-8%29+-+%282u%5E4-8u%5E3%29+ dont forget to distribute the negative
+2u%5E4-5u%5E3-12u%5E2%2B2u-8-2u%5E4%2B8u%5E3+
When you combine like terms ...
+3u%5E3-12u%5E2%2B2u-8+
notice that the first term cancels. We did this on purpose.
continue on as we did in the the first step, this time asking: what number times u equals 3u^3? The answer: 3u^2
Multiply that value by the denominator.
+highlight%283u%5E2%29+%28u-4%29+=+3u%5E3-12u%5E2+ subtract this answer once again.
+3u%5E3-12u%5E2%2B2u-8+-+%283u%5E3-12u%5E2%29+ watch the negatives
+3u%5E3-12u%5E2%2B2u-8-3u%5E3%2B12u%5E2+ combine like terms.
+-12u%5E2%2B2u-8%2B12u%5E2+ notice that TWO terms will cancel in this step
+2u-8+ back to step one:
What number times u equals 2u? The answer is 2.
Multiply it by the denominator.
+highlight%282%29%28u-4%29+=+2u-8+
Subtract this value from what remains.
+2u-8+-+%282u-8%29+ watch the negatives ....
+2u+-8+-+2u+%2B+8+ EVERYTHING cancels.
This means there is NO remainder.
Lets look at the numbers we came up with in each "First step" (the highlighted numbers)
+2u%5E3+ and +3u%5E2+ and +2+
Add these numbers together
+2u%5E3+%2B+3u%5E2+%2B+2+ this is your answer