Value of k , if x -1 is a factor of p(x) in this case : p(x)=x^{2}+x+k .

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2. Polynomials

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Find the value of $k$, if $x -1$ is a factor of $p(x)$ in this case : $p(x)=x^{2}+x+k$.

A

$0$

B

$3$

C

$2$

D

$-2$

Solution

Here $p ( x )= x ^{2}+ x + k$

For $x-1$ be a factor of $p(x), \,p(1)$ should be equal to $0$.

We have $p (1)=(1)^{2}+1+ k $ or $p (1)=1+1+ k = k +2$

$\therefore k+2=0$ $\Rightarrow k =-2$

Standard 9

Mathematics

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