Problem

3. Given f(x)=3x^2-9x+k, and the remainder when f(x) is divided by x+1 is 14 , then what is the value of k?

Answer

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Answer

Final Answer: The value of \(k\) is \(\boxed{2}\).

Steps

Step 1 :Given the function \(f(x)=3x^2-9x+k\), and the remainder when \(f(x)\) is divided by \(x+1\) is 14.

Step 2 :According to the remainder theorem, the remainder of a polynomial \(f(x)\) divided by a linear divisor \(x-a\) is equal to \(f(a)\). In this case, the divisor is \(x+1\), so \(a=-1\).

Step 3 :The remainder when \(f(x)\) is divided by \(x+1\) is 14, so \(f(-1)=14\).

Step 4 :We can substitute \(x=-1\) into the equation \(f(x)=3x^2-9x+k\) to find the value of \(k\).

Step 5 :After substituting, we find that \(k=2\).

Step 6 :Final Answer: The value of \(k\) is \(\boxed{2}\).

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