How do you solve x2+x6>0?

1 Answer
Jan 6, 2017

The answer is x],3[]2,[

Explanation:

We start by factorising the expression

x2+x6=(x2)(x+3)

and

let f(x)=(x2)(x+3)

Now, we can make the sign chart

aaaaxaaaaaaaa3aaaaa2aaaa+

aaaax+3aaaaaaaaaa+aaaa+

aaaax2aaaaaaaaaaaaaa+

aaaaf(x)aaaaaaa+aaaaaaaa+

Therefore,

f(x)>0, when x],3[]2,[