Functions Q (1 Viewer)

[Aysce]

Alright I had this functions question and I've never really seen it before so here it is:

f(x) = 3 -1 <= 2 <= 4

f(x)= x^3 +2 5 < 7 < 10

I checked the question and these are the proper figures so it says, Find one domain for both of these functions along with the range.

 

[hscishard]

I've never seen a function like that before wtf
3-1 = 2 <=2 <=4 uhhh it's true
x^3 + 2 5<7<10?

 

[nightweaver066]

Are you sure you typed it up correctly?

Perhaps scan it so we know the exact layout of the question because the way you typed it seems a bit obscure.

 

[SpiralFlex]

Where did you get this question from?

 

[Aysce]

Given inequality:





Given inequality:

Should be clearer now, so yeah you have to find a common domain from these two functions and also the range

 

[hscishard]

wtf...
domain is x=1 range is y=3
That's all I got from the question

 

[SpiralFlex]

Are you sure? There should be variables inside the inequality. Even then the question itself is weird.

 

[Aysce]

Yeah I just copied off the paper itself, checked it. But basically what I need to understand is the concept behind it, because I've never seen a question where they give you two separate functions along with these inequalities to find both the domain and range? :S Unless you have a question even remotely similar to that Spi?

 

[SpiralFlex]

Yeah I just copied off the paper itself, checked it. But basically what I need to understand is the concept behind it, because I've never seen a question where they give you two separate functions along with these inequalities to find both the domain and range? :S Unless you have a question even remotely similar to that Spi?

I have never seen these questions either. But if there was a variable inside the given inequality, then it might be achievable. But the question would be redundant. What paper is this?

 

[Aysce]

It's in my school paper, but what if we changed the question and added the variable in? Just wanna know how to do it incase it pops up in my 2u exam tmr

 

[SpiralFlex]

It's in my school paper, but what if we changed the question and added the variable in? Just wanna know how to do it incase it pops up in my 2u exam tmr

If there is a variable or inside the given inequality, it would be wise to sketch each graph and see the restriction points, marking down the end points of the function. Then prehaps using a number line to see where the inequality holds itself. But again, there would not be much point. Also, was there another part to this question?

 

[Aysce]

Hmm apparently when you find the common domain for both of the given functions, you had to sub in the lowest number from the first inequality into the first function and the highest number from the second inequality into the second function. Ugh, this doesn't make any sense.

 

[SpiralFlex]

Hmm apparently when you find the common domain for both of the given functions, you had to sub in the lowest number from the first inequality into the first function and the highest number from the second inequality into the second function. Ugh, this doesn't make any sense.

Yes, however for certain cases namely parabolas, the end points of the range of the function in the given domain is not necessarily the highest/lowest value. It can be the vertex too. Now, I still stand by my case that you typed the question incorrectly. Check again.