How do you evaluate f(x)=3x^5-2x^2+xf(x)=3x52x2+x at x=2 using direct substitution and synthetic division?

1 Answer
Mar 8, 2017

at x=2x=2, 3x^5-2x^2+x=color(green)(90)3x52x2+x=90
(see below for methods of evaluation)

Explanation:

By direct substitution
At x=2x=2
color(white)("XXX"){: (3x^5,=,3xx32=,96), (-2x^2,=,,-8), (x,=,,underline(2)), (,,,color(green)(90)) :}

By synthetic division

{: (,,x^5,x^4,x^3,x^2,x^1,x^0), (," | ",3,+0,+0,-2,+1,+0), (underline(color(white)("XXX")),underline(" | "),underline(color(white)("XX")),underline(6),underline(12),underline(24),underline(44),underline(90)), (2xx," | ",3,6,12,22,45,color(green)(90)) :}