Question

Factor 2x^2+ 8 or is prime?

Answer 1

Given a quadratic expression of the form

`ax^2+b`

We can factor it by:

`ax^2+b=0`

And solve for x:

`x=\pm\sqrt{-(b)/(a)}`

But, if we try to apply this in the given equation:

`2x^2+8=0`
`\begin{gathered} 2x^2=-8 \\ . \\ x^2=-(8)/(2) \\ . \\ x=\pm√(-4) \end{gathered}`

Which is not a real number. Thus, the expression is prime.