How do you use synthetic division to divide (4x^2 - 2x + 6)(4x22x+6) by 2x-32x3?

1 Answer
Oct 20, 2015

(4x^2-2x+6) div (2x-3) = (2x+2) R:12(4x22x+6)÷(2x3)=(2x+2)R:12

Explanation:

(color(brown)(4)x^2color(brown)(-2)xcolor(brown)(+6))div (color(cyan)(2)xcolor(blue)(-3))(4x22x+6)÷(2x3)

Remember to reverse the sign on color(blue)((-3))(3)
and since we have a non-monic divisor, we need to divide each column sum by (in this case) color(cyan)(2)2
"Bring down" the first coefficient
Then divide by 2
{: ( ," | ",color(brown)(4),color(brown)(-2),color(brown)(+6)), (color(blue)(+3)," | ", , , ), ( ," | ","----","----","----"), (color(cyan)(/2)," | ",4,,), (," | ",2,color(white)("X")2,) :}

Multiply the last column quotient (2) by 3 and write in the next column.
Add that column.
{: ( ," | ",4,-2,+6), (+3," | ", , color(white)("X")6 , ), ( ," | ","----","----","----"), (/2," | ",4,color(white)("X")4,), (," | ",2,,) :}

Repeat this process until done
{: ( ," | ",4,-2,+6), (+3," | ", , color(white)("X")6 , color(white)("X")6), ( ," | ","----","----","----"), (/2," | ",4,color(white)("X")4,color(white)("X")color(red)(12)), (," | ",color(green)(2),color(white)("X")color(orange)(2),) :}

The last sum (undivided), color(red)(12), is the remainder.
The quotients preceding the last column, color(green)(2) and color(orange)(2), are the coefficients of the quotient expression.

That is the solution is
color(green)(2)x+color(orange)(2) with a Remainder of color(red)(12)