Answer:
A=2
B=-3
C=-5
Step-by-step explanation:
The highiest coefficient in degree of the polynomial is 2 on the left and 1*A*1,
A=2
Let's make the synthetical division:
[tex]\boxed{A=2}\\\begin{array}{c|c|c|c|c|c}&x^4&x^3&x^2&x&1\\---&---&---&---&---&---\\&2&-13&19&5&1\\x=4&&8&-20&-4&4\\&2&-5&-1&1&-5\Longrightarrow \boxed{C=-5}\\x=-\frac{1}{2}&-1&3&-1&\\2&-6&2&&\\---&---&---&---&---&---\\\end {array}\\\\\\\boxed{2x^4-13x^3+19x^2+5x+1=(x-4)(2x+1)(x^2-3x+1)-5}\\\\\\\boxed{B=-3}\\[/tex]