Solve for q: Polynomial Factors Homework

AI Thread Summary
To solve for q in the polynomial f(x) = x^3 + qx^2 - x - 2, it is necessary to find the remainders of f(x) when divided by x + 1 and x - 2. Evaluating f(-1) and f(2) will yield expressions that include q. The key point is that these two remainders must be equal, leading to an equation that can be solved for q. Understanding polynomial division and evaluating the function at specific points is crucial for finding the solution. The discussion emphasizes that working with the variable q should not be intimidating.
DanialD
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Homework Statement


If we divide f(x)= x^3+qx^2-x-2 by x+1, we get the same remainder as if we divide it by x-2. Determine the value of q


Homework Equations



f(x)= x^3+qx^2-x-2

The Attempt at a Solution



I tried to plug in f(-1) into the equation, and then f(2) into the equation.. But i honestly do not understand how to go about finding the remainders.
 
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Is it because you don't know how to divide polynomials? Or are you intimidated by having q as a coefficient?
 
well yeah, i don't know what to do with q.
 
Don't be afraid of the q. If you evaluated f(-1), you should get an expression with q as the single variable. Likewise, you'll get another expression after evaluating f(2). Now, what do you know about f(-1) and f(2)?


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I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
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