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# Need help with c2 questions watch

1. 1)Does anyone know how to draw the graph y=x+(3/x)? What does the x do ?? 2) how do you sketch this? Y=(x+k)^2-9,k>0 thanks for the help I am really stuck
2. Also could anyone explain this? f3 I don't get which length I am supposed this find and I did this Attachment 473251473253
Attached Images

3. y=(x+3)/x is the same as y=3/x +1
4. (Original post by coconut64)
1)Does anyone know how to draw the graph y=x+3/x? What does the x do ?? 2) how do you sketch this? Y=(x+k)^2-9,k>0 thanks for the help I am really stuck
For your first question, you may wish to plug in numbers that give you nice outputs like x = 1, x = 0.5 etc and see if you can spot the shape, which is similar to 1/x.

For your second question, think about the different distinct points on the graph (Where is the maximum/minimum, when is y =0, when is x =0?) and think about how that helps.
5. (Original post by coconut64)
1)Does anyone know how to draw the graph y=x+3/x? What does the x do ?? 2) how do you sketch this? Y=(x+k)^2-9,k>0 thanks for the help I am really stuck
Y = (x+3)/x is the same as y = 1 + 3/x (so is a translation. At this point consider Y = 3/x and draw the graph, what would happen if we add 1)

The second queation is basically the same except with have k being added to x. First consider Y = x^2 -9 and plot this graph Using the interval [-3,3], what would happen if we add a number k to x? Try making k equals 2 and do the same thing as before, and compare both answers.
6. (Original post by whydoidothis?)
y=(x+3)/x is the same as y=3/x +1
No I mean y=x+(3/x), thanks
7. find the intercepts then sketch the graph (pay careful attention to the function transformations to make sure you get the positions right). also to find the length of the tangents, just use Pythagoras' theorem.
8. (Original post by kkboyk)
Y = (x+3)/x is the same as y = 1 + 3/x (so is a translation. At this point consider Y = 3/x and draw the graph, what would happen if we add 1)

The second queation is basically the same except with have k being added to x. First consider Y = x^2 -9 and plot this graph Using the interval [-3,3], what would happen if we add a number k to x? Try making k equals 2 and do the same thing as before, and compare both answers.
Hi, it is x+(3/x )thanksr
9. (Original post by coconut64)
Hi, it is x+(3+x)/x thanks
Is it or ? You have said both.
10. (Original post by ombtom)
Is it or ? You have said both.
This has just got confusing
11. (Original post by kkboyk)
This has just got confusing
I initially thought it was
12. (Original post by ombtom)
Is it or ? You have said both.
Sorry, I just realise it is y=x+(3/x)
13. (Original post by ombtom)
I initially thought it was
Sorry guys it is actually y=x+(3/X)
14. (Original post by coconut64)
Sorry, I just realise it is y=x+(3)/x
Try drawing y=x and y=3/x separate on the same graph to help you visualise
15. (Original post by kkboyk)
Y = (x+3)/x is the same as y = 1 + 3/x (so is a translation. At this point consider Y = 3/x and draw the graph, what would happen if we add 1)

The second queation is basically the same except with have k being added to x. First consider Y = x^2 -9 and plot this graph Using the interval [-3,3], what would happen if we add a number k to x? Try making k equals 2 and do the same thing as before, and compare both answers.
Why doyou make k =2?
16. (Original post by SeanFM)
For your first question, you may wish to plug in numbers that give you nice outputs like x = 1, x = 0.5 etc and see if you can spot the shape, which is similar to 1/x.

For your second question, think about the different distinct points on the graph (Where is the maximum/minimum, when is y =0, when is x =0?) and think about how that helps.
Thanks for the reply but how do you work out k?
17. (Original post by coconut64)
Why doyou make k =2?
Just to make you visualise what would happen for any values of k (it will translate to the left for every positive value of K)
18. (Original post by coconut64)
Thanks for the reply but how do you work out k?
You don't - k is any positive number in this case (it says k>0) so it wants you to have things in terms of k.

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