Question #123b8

1 Answer
Aug 12, 2017

{x in RR: -6<= x <= 1}

Explanation:

In the realm of real numbers, the radicand must be positive (the square root of negative numbers is a nonreal quantity).

We can factor the radicand into

ul(sqrt(-(x+6)(x-1))

We see that the function equals 0 when x = -6 and x = 1, so what we need to do is figure out if the domain is real in between these two numbers or outside of these values.

Plugging in a value between -1 and 6 (let's say 0):

-(0+6)(0-1) = color(red)(6

Since it is positive, we know the domain is at least

-6<= x <= 1

Plugging in -7 and 2 yields

-(-7+6)(-7-1) = -8

-(2+6)(2-1) = -8

Since these are both negative, our final domain is

color(blue)(ulbar(|stackrel(" ")(" "{x in RR: -6<= x <= 1}" ")|)

(The domain is all real numbers such that x is greater than or equal to -6 and less than or equal to 1).