How do you synthetic division and the Remainder Theorem to find P(–3) if P(x)=x4+19x3+108x2+236x+176?

1 Answer
Jul 11, 2018

The remainder is 8 and the quotient is =x3+16x2+60x+56

Explanation:

Let's perform the synthetic division

aaaa3aaaa1aaaa19aaaaaa108aaaa236aaaaa176

aaaaaaaaaaaaaaa3aaaaa48aaa180aaa168

aaaaaaaaa_________________________________________________________##

aaaaaaaaaaa1aaaa16aaaaaa60aaaaaa56aaaaaa8

The remainder is 8 and the quotient is =x3+16x2+60x+56

Apply the remainder theorem for verification

When a polynomial f(x) is divided by (xc), we get

f(x)=(xc)q(x)+r

Let x=c

Then,

f(c)=0+r

Here,

f(x)=x4+19x3+108x2+236x+176

Therefore,

f(3)=(3)4+19(3)3+108(3)2+236(3)+176

=8

The remainder is =8