A0W0N
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Equation of curve: y=2x+x^2 -4^3
I found the turning points and they're (-1,-4) and (-3,0)
But whem i put thw equation into a graphing calculator there are different points. I differentiated the equation to get 3x^2 +12x+9.
I appreciate any help, Thanks
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Pangol
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(Original post by A0W0N)
Equation of curve: y=2x+x^2 -4^3
I found the turning points and they're (-1,-4) and (-3,0)
But whem i put thw equation into a graphing calculator there are different points. I differentiated the equation to get 3x^2 +12x+9.
I appreciate any help, Thanks
That differential doesn't match your curve equation. Can you check the question and let us know what it says?
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A0W0N
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(Original post by Pangol)
That differential doesn't match your curve equation. Can you check the question and let us know what it says?
Yes thats the correct equation have i differentiated it wrong?
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ghostwalker
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(Original post by A0W0N)
Yes thats the correct equation have i differentiated it wrong?
As Pangol said, the curve doesn't match the deriviative, but more than that the initial equation looks weird with the -4^3 at the end. Can you upload an image of the original question so we can be certain?
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David Getling
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(Original post by A0W0N)
Equation of curve: y=2x+x^2 -4^3
I found the turning points and they're (-1,-4) and (-3,0)
But whem i put thw equation into a graphing calculator there are different points. I differentiated the equation to get 3x^2 +12x+9.
I appreciate any help, Thanks
At any rate, well done for having the sense to check your answer with a graphics calculator. In the exam this would have helped you spot your mistake, maybe correct it, and get a few more marks. Far too many ignorant teachers tell students that GDCs aren't worth having. You've just provided one (of very many) example of how important it is to have one, and know how to use it.
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A0W0N
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Name:  60891EE6-09D1-4C0F-95B1-03630A630FE1.jpeg
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Size:  23.3 KBName:  60891EE6-09D1-4C0F-95B1-03630A630FE1.jpeg
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Pangol
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(Original post by A0W0N)
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That really helps. Can you explain how you get your dy/dx? You say you get 3x^2 +12x+9 - how do you get this?
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A0W0N
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(Original post by Pangol)
That really helps. Can you explain how you get your dy/dx? You say you get 3x^2 +12x+9 - how do you get this?
I multiplyed it by the powers then multiplyed it by (-1) so i could try and factorise it
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A0W0N
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(Original post by Pangol)
That really helps. Can you explain how you get your dy/dx? You say you get 3x^2 +12x+9 - how do you get this?
i redid it and got 2+2x-12x^2
I have no idea how i got that answer i apologize
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A0W0N
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(Original post by A0W0N)
i redid it and got 2+2x-12x^2
I have no idea how i got that answer i apologize
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Edit: I now have the correct turning points i just ont know how to find the the nature of them and i can't differenciate twice
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A0W0N
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I figured it out thanks everyone for the help!
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