Question

if x+2 is a factor of 3x^3+px-8 then find p​

Answer 1

p=-16

Step-by-step explanation:

when (x+2)is a factor of 3x³+px-8,

Soln

comparing x+2 with x-a ,

or,x=-2

putting x in the equation,

p(x)=3x³+px-8

or,p(-2)=3x³+px-8

or,0=3*(-2)³+p*(-2)-8

[since x+2 is a factor, it reduces the equation to 0 so we can put

0 in place of p(-2) ]

or, 0=3*-8+(-2)*p-8

or,0=-24-8-2p

or,2p=-32

or, p=32/2

•°•p=-16

HOPE IT HELPS :)