Question: TSSM 2006 Exam 1. Graphs and Relations Module. Q3.

[ausyid]

Anyone worked out how to answer this ridiculous question?

I can scan it if people don't have it themselves.

It's the one about the graph of y versus x^3.

Thanks.

[vce01]

haven't got it, could you scan it?

and in an unrelated question, you don't go on bigfooty, do you?

[ausyid]

I do go on BF actually What's your username on there?

Here is the question:



The answer is apparently C, but they give no explanation.

[Collin Li]

Let , so now you are looking at a graph.

Notice that it is a straight line:



You have enough data to solve for and .

You'll get:

Now substitute back in when you're done.

[ausyid]

You make it look so simple.

My teacher couldn't solve this question.

Thanks for the help.

[Collin Li]

No problem.

It's an important scientific technique for establishing empirical models. For example, if I believe that the relationship between something is an inverse relationship, i.e: , then I could do an experiment to get some data, plot the points, and try to fit it to such a curve.

A much better way to do this (especially without computers), is to let:

Re-tabulate your data in terms of and instead (plotting and , essentially), and hopefully you should be able to draw a line of best fit to get a straight-line equation that confirms your model: .

[ReVeL]

You make it look so simple.

My teacher couldn't solve this question.

Thanks for the help.

Lol at that.

[ilovesuck]

Let , so now you are looking at a graph.

Notice that it is a straight line:



You have enough data to solve for and .

You'll get:

Now substitute back in when you're done.

hm, i still dont get it

how did you get y = x^3 - 15 ?

i keep coming up with the answer: y = x^3 + 5   .. .. and thats not even one of the answers


this is really frustrating, since it SHOULD be easy sodafjwern

[ausyid]

On closer inspection, I'm not quite sure you get y = z - 15 but rather y = z + 5. Or am I wrong?

[ausyid]

Let , so now you are looking at a graph.

Notice that it is a straight line:



You have enough data to solve for and .

You'll get:

Now substitute back in when you're done.

hm, i still dont get it

how did you get y = x^3 - 15 ?

i keep coming up with the answer: y = x^3 + 5   .. .. and thats not even one of the answers


this is really frustrating, since it SHOULD be easy sodafjwern

You posted while I was posting!

I knew there was a reason why I couldn't get the answer. I kept getting y = x^3 + 5 as well.

[Collin Li]

Hmm... I agree. I didn't actually check the line's equation, to be honest. LOL

Yeah, I got that too!

[ReVeL]

Same.

Must just be a shitty question.

[Noblesse]

I got that too

Anyone who does Accounting knows how many mistakes TSSM makes in those (a HEAP)
So it could be a mistake...

[Collin Li]

I didn't notice this was in the Further thread, and this was part of the graphs and relations module, otherwise I wouldn't have posted that mini-story about how scientists use this method to figure out equations... thought it was Methods. Oops!

[Noblesse]

What, are you saying us Further people can't cope?


...


*head explodes*