Question

If (x + 1) is factor of polynomial - 2x² + 3x tk then find the value of k.​

Answer 1

(i) x

2

+x+k=0⇒(1)

2

+1+k=0⇒1+1+k=0⇒k=−2

(ii) 2x

2

+kx+

2

=0⇒2(1)

2

+k(1)+

2

=0⇒2+k+

2

=0⇒k=−2−

2

(iii) kx

2

−

2

x+1=0⇒k(1)

2

−

2

(1)+1=0⇒k−

2

+1=0⇒k=

2

−1

(iv) kx

2

−3x+k=0⇒k(1)

2

−3(1)+k=0⇒k−3+k=0⇒2k=−3⇒k=−

2

3

Answer 2

Answer:

since ( x+1) is a factor , x+1=0 which gives x= -1

now substitute the value of x in the given polynomial.

-2 ( - 1 )2 + 3 ( -1 ) + k =0

-2-3+k=0

-5 +k =0

k = 5