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Solve 3x^3 +2x^2 +15 divided by (x+2) show step by step

1 Answer

6 votes

Answer:

3x^2-4x+8 (R -1)

Explanation:

We can use synthetic division:

-2 | 3 2 0 15

____-6 8 -16

3 -4 8 | -1

So basically, you solve x+2=0 (which is x=-2) and then you put it on the left side. Then make a line and put the coefficients of the polynomial you want to divide. Then with the first coefficient it gets dropped. You would then multiply this by -2 (so 3*-2=-6) and then combine it with 2 in the second column (2+-6=-4). Then we do the same thing with the third column (-4*-2=8) and combine (0+8=8). Same with the fourth column (8*-2=-16) but when we combine this time the answer will be our remainder (15+-16=-1).

So how you would read your final answer is 3x^2-4x+8 (R -1) which the numbers you get are the coefficients.

User Nils Landt
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