Question

3) If '2' is a zero of the polynomial x2+2x-4a then find the value of 'a'?​

Answer 1

Answer:

Let p(x)=ax

3

+x

2

−2x+4a−9

As (x+1) is a factor of p(x)

∴p(−1)=0 [By factor theorem]

⇒a(−1)

3

+(−1)

2

−2(−1)+4a−9=0

⇒a(−1)+1+2+4a−9=0

⇒−a+4a−6=0

⇒3a−6=0⇒3a=6⇒a=2