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#1 2024-05-17 08:04:37
- mathxyz
- Member
- From: Brooklyn, NY
- Registered: 2024-02-24
- Posts: 1,053
Long Division
It is hard to show the work without a photo or Latex for long division.
(4x^3 - 3x^2 + x + 1) ÷ (x + 2)
My answer is 4x^2 - 11x + 2 with remainder -3.
According to the book, the remainder is -45.
How can that be?
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#2 2024-05-17 20:16:26
- Bob
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- Registered: 2010-06-20
- Posts: 10,627
Re: Long Division
I'll trying to set this out here. The alignment may get a little messed up.
(4x^3 - 3x^2 + x + 1) ÷ (x + 2)
4x^2 -11x +23
_____________________________________
x+2 | 4x^3 - 3x^2 + x + 1
4x^3 +8x^2
_______________
-11x^2 +x
-11x^2 -22x
________________
+23x + 1
+23x +46
______________
remainder = - 45
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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#3 2024-05-18 02:29:11
- mathxyz
- Member
- From: Brooklyn, NY
- Registered: 2024-02-24
- Posts: 1,053
Re: Long Division
I'll trying to set this out here. The alignment may get a little messed up.
(4x^3 - 3x^2 + x + 1) ÷ (x + 2)
4x^2 -11x +23
_____________________________________
x+2 | 4x^3 - 3x^2 + x + 14x^3 +8x^2
_______________-11x^2 +x
-11x^2 -22x
________________+23x + 1
+23x +46
______________remainder = - 45
Bob
Thank you very much. This is problem 89 on page 49.
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