Question

If one of the zeroes of polynomial 2x2+px+4 is 2 find the other root and also find p

Answer 1

Answer:

Suppose, f(x)= 2x^2+px + 4

So, f(2)= 8 + 2p + 4= 2p+12

Now, 2p+12=0

or, 2p= -12

or, p= -6

Hence required polynomial is, 2x^2+ 6x + 4

So, 2x^2 - 6x + 4 = 0

or, 2x^2 - 4x - 2x + 4 =0

or, 2x(x - 2) + 2(x- 2)=0

or, (2x + 2)(x-2)=0

or, (2x+2)=0. or, (x-2)=0

or, x=-1 or x= 2