Question

X + 1 is a factor of the polynomial x cube + a square minus x + 1

Answer 1

Answer:

If X+1 is factor of

${x}^{3} + a {x}^{2} - x + 1$

then X = -1 is zero of polynomial

so putting x= -1 in polynomial

$( { - 1})^{3} + a( { - 1})^{2} - ( - 1) + 1 = 0$

$- 1 + a + 1 + 1 = 0$

$so \: a = - 1$