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If f(x)=x^5-x^2, then what is the remainder when f(x) is divided by x+1

User Dizy
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2 Answers

4 votes
It’s very simple
Equate the x+ 1 = 0
So x= -1
Put -1 into x^5 - x^2
So f(-1)= (-1)^5 - (-1)^2
= -2
It hope it helped :)
This is the simplest way of getting the remainder. So the reminder is -2
User Shinobu
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5.2k points
5 votes

Answer: -2

========================================================

Reason:

We'll use the remainder theorem. When dividing the polynomial function p(x) by x-k, the remainder is p(k).

Comparing x+1 to x-k, we see that k = -1. It might help to think of x+1 as x-(-1).

Plug this k value into the function to find the remainder when dividing by x+1.

So,

f(x) = x^5-x^2

f(-1) = (-1)^5 - (-1)^2

f(-1) = -1 - 1

f(-1) = -2

The remainder is -2

This can be confirmed through use of either synthetic division or polynomial long division as shown in the diagrams below. Synthetic division is the better option in my opinion.

If f(x)=x^5-x^2, then what is the remainder when f(x) is divided by x+1-example-1
If f(x)=x^5-x^2, then what is the remainder when f(x) is divided by x+1-example-2
User Chris Greenwood
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5.1k points