How do you find the domain and range of 13x(x2)1?

1 Answer
May 29, 2017

The domain is x(1,0](+1,+)
The range is y[0,+)

Explanation:

What's uner the sign is 0

So,

13xx210

13x(x+1)(x1)0

Let f(x)=13x(x+1)(x1)

We can build a sign chart

aaaaxaaaaaaaaa1aaaaa0aaaaaaa+1aaaa+

aaaax+1aaaaaaaaaa+aaaa+aaaaaa+

aaaaxaaaaaaaaaaaaaaaaa+aaaaaa+

aaaax1aaaaaaaaaaaaaaaaaaaa+

aaaaf(x)aaaaaaaaaaa+aaaaaaaaaa+

Therefore,

f(x)0 when x(1,0](+1,+)

The domain is x(1,0](+1,+)

Let,

y=13xx21

When x=1, , y=+

When x=0, , y=0

The range is y[0,+)