How do you factor 2k^2+4k+8?

Question

I am stuck on this one. And we haven't learned quadratic formula yet.

Answer 1

Jed,

        The first thing to notice is that you can factor out a 2 which gives 2*(k²+2k+4) but the quantity in ( ) has no real factors?? Are you sure of the coefficients and signs?

 

Jim

 

Answer 2

first factor out the 2 

 

2 ( K^2 + 2k + 4 ) = 0

 

k^2 + 2k + 4 = 0

 

you are going to have to use the quadratic formula on this unfortunately 

 

 

let k = -2 +/-  sqrt ( 4 - 16) /  2

 

 

=[ -2 + sqrt (-12) ] / 2           and  [  -2 - sqrt -12 ] / 2 

 

remember that sqrt of -1 is known as i

 

[-2 + 2sqrt 3i] / 2 and [-2 - 2sqrt 3i] / 2

 

-1 + sqrt 3i  and -1 - sqrt 3i those are your answers