How do you simplify and divide (y^3+3y^2-5y-4)/(y+4)y3+3y25y4y+4?

2 Answers
Jul 5, 2017

The quotient is =y^2-y-1=y2y1

Explanation:

Let's perform the synthetic division

color(white)(aaaa)aaaa-44color(white)(aaaa)aaaa|color(white)(aaaa)aaaa11color(white)(aaaa)aaaa33color(white)(aaaaa)aaaaa-55color(white)(aaaa)aaaa-44
color(white)(aaaaaaaaaaaa)aaaaaaaaaaaa_________

color(white)(aaaa)aaaacolor(white)(aaaaaaa)aaaaaaa|color(white)(aaaa)aaaacolor(white)(aaa)aaa-44color(white)(aaaaaa)aaaaaa44color(white)(aaaaaa)aaaaaa44
color(white)(aaaaaaaaaaaa)aaaaaaaaaaaa________

color(white)(aaaa)aaaacolor(white)(aaaaaaa)aaaaaaa|color(white)(aaa)aaa11color(white)(aaa)aaa-11color(white)(aaaaa)aaaaa-11color(white)(aaaaaa)aaaaaacolor(red)(0)0

The remainder is 00 and the quotient is =y^2-y-1=y2y1

(y^3+3y^2-5y-4)/(y+4)=y^2-y-1y3+3y25y4y+4=y2y1

Jul 5, 2017

y^2-y-1y2y1

Explanation:

"one way is to use the divisor as a factor in the numerator"one way is to use the divisor as a factor in the numerator

"consider the numerator"consider the numerator

color(red)(y^2)(y+4)color(magenta)(-4y^2)+3y^2-5y-4y2(y+4)4y2+3y25y4

=color(red)(y^2)(y+4)color(red)(-y)(y+4)color(magenta)(+4y)-5y-4=y2(y+4)y(y+4)+4y5y4

=color(red)(y^2)(y+4)color(red)(-y)(y+4)color(red)(-1)(y+4)color(magenta)(+4)-4=y2(y+4)y(y+4)1(y+4)+44

=color(red)(y^2)(y+4)color(red)(-y)(y+4)color(red)(-1)(y+4)+0=y2(y+4)y(y+4)1(y+4)+0

rArr(cancel((y+4))(color(red)(y^2-y-1)))/cancel((y+4))

=y^2-y-1larr" quotient"