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Find the remainder when f(x) is divided by (x - k).

f(x) = 7x4 + 12x3 + 6x2 - 5x + 16; k = 3

User Mckenna
by
5.7k points

1 Answer

2 votes

Answer:

946

Explanation:

To find just the remainder when dividing a polynomial by x-3, you could just plug in 3 into that polynomial.

If you were dividing by x+3, the remainder would just be the polynomial evaluated at x=-3.

Anyways plugging in 3 gives

7(3)^4 + 12(3)^3 + 6(3)^2 - 5(3) + 16

Just put this into your nearest calculator .

It should output 946.

You could use synthetic division or even long.

Synthetic Division.

We put 3 on outside because we are dividing by x-3.

3. | 7. 12. 6. -5. 16

| 21. 99. 315. 930

________________________

7. 33. 105. 310. 946

The remainder is the last number in the last column.

The plugging in and the synthetic division will always work when dividing by a linear expression.

User Borassign
by
6.0k points