Circle and semi circle question (1 Viewer)

kpad5991

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I know how to sketch any circle however the question says sketch the coordinates of any points that have integer coordinates. How would you work that out for the following

x^2 + y^2 = 5

And y = root 2-x^2
 

eyeseeyou

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I know how to sketch any circle however the question says sketch the coordinates of any points that have integer coordinates. How would you work that out for the following

x^2 + y^2 = 5

And y = root 2-x^2
x^2+y^2=5 is common sense

Use the rule that x^2+y^2=r^2

r^2=5

therefore r^2= root 5

Draw a circle with the origin being the centre and draw a circle labelling all the necessary coordinates

https://www.google.com.au/search?q=...hVF2LwKHRu9D_oQ_AUIBigB#imgrc=arl4uR3WItosDM:

As for the second question I need you to be clearer, is it y= root (2-x^2) or y=root (2) -x^2 ?
 

pikachu975

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x^2+y^2=5 is common sense

Use the rule that x^2+y^2=r^2

r^2=5

therefore r^2= root 5

Draw a circle with the origin being the centre and draw a circle labelling all the necessary coordinates

https://www.google.com.au/search?q=...hVF2LwKHRu9D_oQ_AUIBigB#imgrc=arl4uR3WItosDM:

As for the second question I need you to be clearer, is it y= root (2-x^2) or y=root (2) -x^2 ?
You didn't even answer the question, he asked how do you find the INTEGER coordinates and all you did was tell him that the radius was irrational (root 5) which didn't help at all.
 

eyeseeyou

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You didn't even answer the question, he asked how do you find the INTEGER coordinates and all you did was tell him that the radius was irrational (root 5) which didn't help at all.
Whoops yeah soz idk
 

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I know how to sketch any circle however the question says sketch the coordinates of any points that have integer coordinates. How would you work that out for the following

x^2 + y^2 = 5

And y = root 2-x^2
 
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pikachu975

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x^2+y^2=5 is common sense

Use the rule that x^2+y^2=r^2

r^2=5

therefore r^2= root 5

Draw a circle with the origin being the centre and draw a circle labelling all the necessary coordinates

https://www.google.com.au/search?q=...hVF2LwKHRu9D_oQ_AUIBigB#imgrc=arl4uR3WItosDM:

As for the second question I need you to be clearer, is it y= root (2-x^2) or y=root (2) -x^2 ?
Just a note, the whole equation is under square root as a semicircle equation is sqrt(r^2 - x^2)
 

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