Question

Show that x-1 is a factor of the polynomial x3-23x2+142x-120. hence factorise the following

Answer 1

X-1 is a factor of the given polynomial
therefore, zero of (X-1) will be X-1=0
therefore X=+1
p(1)= x3 -23X2+142X-120
= 1(3)* -23(1)* +142(1) -120
= 1-23+142-120
= -22+142-120
= -22+22
=0
p(1)=0
therefore, X-1 is a factor of the given polynomial