Question

What is the domain of this. I got x cant equal 3 and -3.

Answer 1

umm i cant do the equation, but here it is. I'm trying my best. y=x+3/4-sqr (x^2-9)

Answer 2

The equation is

\[\large y = \frac{x+3}{4-\sqrt{x^2-9}}\]

right?

Answer 3

yea, it doesnt show as an equation when i write it on here tho. but i think u got it right

Answer 4

so the equation given to you is in text form like that?

Answer 5

no no. the system on here is showing it in text

Answer 6

but what I wrote is what they gave you?

Answer 7

yes

Answer 8

ok you first need to solve

x^2 - 9 >= 0

for x

Answer 9

i did i got -3 and 3

Answer 10

that's if you solve x^2 - 9 = 0

Answer 11

it's slightly different solving x^2 - 9 >= 0 , but -3 and 3 are involved

Answer 12

a visual way to solve x^2 - 9 >= 0 is to look at the graph of x^2 - 9 and note where it is above the x axis

well this is for the intervals (-infinity, -3) and (3, infinity) and you use a graph to see this

therefore, the solution for x^2 - 9 >= 0 in interval notation is

(-infinity, -3) U (3, infinity)

Answer 13

the last thing you need to do is make sure the denominator is not zero (since you cannot divide by zero)

Answer 14

the answer also gives me 5 and -5

Answer 15

you need to solve \[\large 4-\sqrt{x^2-9}=0\] for x

Answer 16

hopefully you can see how solving that leads you to x = 5 or x = -5

these two values must be excluded from the domain (to avoid division by zero)

Answer 17

ok thank you

Answer 18

yw