Question

If $x^2+ax+2$ has a remainder $1$ when divided by $x-1$, then what will be $a$?

• A. $1$
• B. $-1$
• C. $2$
• D. $-2$

Answer 1

Answer: (D)

$-2$

Replace $x$ as $1$ in the expression:
$x^2+ax+2$
$=$ $1^2+a\left(1\right)+2$
$=1+a+2$
$=3+a$
So, the remainder is $3+a$, Now substitute the value of remainder, we know it is $1$.
$3+a=1$
$a=1-3$
$a=-2$