To divide the polynomial 2 x 3 + 17 x 2 + 23 x − 42 by x − 1 , we can use polynomial long division or synthetic division which both yield the same quotient of 2 x 2 + 19 x + 42 with a remainder of 0. This indicates that x − 1 is a factor of the polynomial.
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Divide the polynomial 2 x 3 + 17 x 2 + 23 x − 42 by x − 1 using polynomial long division or synthetic division.
Performing the division, we find the quotient to be 2 x 2 + 19 x + 42 and the remainder to be 0.
Therefore, 2 x 3 + 17 x 2 + 23 x − 42 = ( x − 1 ) ( 2 x 2 + 19 x + 42 ) .
The result of the division is 2 x 2 + 19 x + 42 .
Explanation
Understanding the Problem We are asked to divide the polynomial 2 x 3 + 17 x 2 + 23 x − 42 by x − 1 . This can be done using polynomial long division or synthetic division. Since the remainder is 0, it means that x − 1 is a factor of the polynomial.
Performing Polynomial Long Division We can perform polynomial long division as follows:
2x^2 + 19x + 42
x - 1 | 2x^3 + 17x^2 + 23x - 42 - (2x^3 - 2x^2) ------------------ 19x^2 + 23x - (19x^2 - 19x) ------------------ 42x - 42 - (42x - 42) ------------------ 0
So, the quotient is 2 x 2 + 19 x + 42 and the remainder is 0.
Performing Synthetic Division Alternatively, we can use synthetic division. We set up the synthetic division table with the coefficients of the polynomial (2, 17, 23, -42) and the root of the divisor x − 1 , which is 1.
2
17
23
-42
1
2
19
42
---
----
----
-----
2
19
42
0
The last number in the bottom row is the remainder, which is 0. The other numbers are the coefficients of the quotient, which is 2 x 2 + 19 x + 42 .
Final Result Therefore, the result of dividing 2 x 3 + 17 x 2 + 23 x − 42 by x − 1 is 2 x 2 + 19 x + 42 .
Examples
Polynomial division is used in various applications, such as finding the roots of a polynomial, simplifying rational expressions, and solving algebraic equations. For example, in engineering, polynomial division can be used to analyze the stability of a system or to design filters. In computer graphics, it can be used to model curves and surfaces. Understanding polynomial division helps in simplifying complex mathematical models in these fields.