Transcript text: Divide $x^{3}+x^{2}-5 x-2$ by $x-2$
Solution
Solution Steps
To divide the polynomial \(x^3 + x^2 - 5x - 2\) by \(x - 2\), we can use polynomial long division or synthetic division. Here, we'll use synthetic division because the divisor is in the form \(x - c\). The steps are as follows:
Identify the coefficients of the dividend polynomial: \(1, 1, -5, -2\).
Use the root of the divisor, which is \(2\), for synthetic division.
Perform synthetic division to find the quotient and remainder.
Step 1: Identify the Polynomial and Divisor
We are given the polynomial \( P(x) = x^3 + x^2 - 5x - 2 \) and we need to divide it by the linear polynomial \( D(x) = x - 2 \).
Step 2: Perform Synthetic Division
Using synthetic division with the root of the divisor \( x - 2 \), which is \( 2 \), we set up the coefficients of the polynomial:
Coefficients: \( [1, 1, -5, -2] \)
We perform the synthetic division:
Bring down the leading coefficient \( 1 \).
Multiply \( 1 \) by \( 2 \) and add to the next coefficient \( 1 \) to get \( 3 \).
Multiply \( 3 \) by \( 2 \) and add to the next coefficient \( -5 \) to get \( 1 \).
Multiply \( 1 \) by \( 2 \) and add to the last coefficient \( -2 \) to get \( 0 \).
The result of the synthetic division gives us:
Quotient: \( Q(x) = x^2 + 3x + 1 \)
Remainder: \( R = 0 \)
Step 3: Write the Result
The division can be expressed as:
\[
P(x) = (x - 2)(x^2 + 3x + 1) + 0
\]
This indicates that \( P(x) \) is exactly divisible by \( D(x) \).
Final Answer
The quotient of the division is \( x^2 + 3x + 1 \) and the remainder is \( 0 \). Thus, the final answer is:
\[
\boxed{Q(x) = x^2 + 3x + 1}
\]