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# Ocr C1 Graph Drawing watch

1. Hi.
Please could someone explain to me why for question 4(ii) it is not suitable to rearrange the equation to draw a graph with a +x^3 instead.
Are they not equivalent?
https://a9497d7f220e174d38d014b2b1d8...20C1%20OCR.pdf
Thanks.
2. (Original post by SamuelN98)
Hi.
Please could someone explain to me why for question 4(ii) it is not suitable to rearrange the equation to draw a graph with a +x^3 instead.
Are they not equivalent?
https://a9497d7f220e174d38d014b2b1d8...20C1%20OCR.pdf
Thanks.
No, they are only equivalent if you had it = 0.

i.e: roots are invariant under reflection. If you were to re-arrange the equation to get +x^3 you've reflected the graph in the x-axis, which is a totally different graph.

However, if you had 4x - 3x^2 + x^3 = 0 - then you can re-arrange it however you like because the roots remain invariant under reflection.
3. (Original post by Zacken)
No, they are only equivalent if you had it = 0.

i.e: roots are invariant under reflection. If you were to re-arrange the equation to get +x^3 you've reflected the graph in the x-axis, which is a totally different graph.

However, if you had 4x - 3x^2 + x^3 = 0 - then you can re-arrange it however you like because the roots remain invariant under reflection.
Thanks!,
what if i had 4x - 3x^2 + x^3 = 7 etc.
can i rearrange it then?
4. (Original post by SamuelN98)
Thanks!,
what if i had 4x - 3x^2 + x^3 = 7 etc.
can i rearrange it then?
Yes, then you can re-arrange it because it's the same thing as 4x - 3x^2 + x^3 - 7 = 0 (i.e: still a root of some equation and hence still invariant).
5. (Original post by Zacken)
Yes, then you can re-arrange it because it's the same thing as 4x - 3x^2 + x^3 - 7 = 0 (i.e: still a root of some equation and hence still invariant).
You`d make a good maths teacher.
Thanks again
6. (Original post by SamuelN98)
You`d make a good maths teacher.
Thanks again
Thank you! That's a compliment if I ever saw one.

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