Dat circle geo (2 Viewers)

[RealiseNothing]

Was the sneakiest thing ever.

 

[bunnypacman]

Are you talking about 13d) ?

 

[lolcatss]

How was it sneaky?

 

[RealiseNothing]

How was it sneaky?

Most of the "obvious" proofs would be invalid.

A lot of people would have assumed it was a straight line and done alternate angles.

 

[RealiseNothing]

Are you talking about 13d) ?

Yes.

 

[Focus is Key]

Most of the "obvious" proofs would be invalid.

A lot of people would have assumed it was a straight line and done alternate angles.

Damn!!!!!!!!!!!!!!!!!!!! I did that

 

[j1mmy_]

Most of the "obvious" proofs would be invalid.

A lot of people would have assumed it was a straight line and done alternate angles.

Oh crap

 

[Magical Kebab]

Most of the "obvious" proofs would be invalid.

A lot of people would have assumed it was a straight line and done alternate angles.

I did that whilst knowing it was wrong coz I had no other method of doing it lol

 

[bunnypacman]

What was the solution?? ><

 

[andrew29223]

Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear

 

[lulwut]

if you did alternate angles from the tangent drawn between the two circles, the proof would be valid right? you're proving that both angles produced from the tangent to their respective lines are equal -> therefore lies on the same line / co-linear.. I think..

 

[RealiseNothing]

Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear

This is what I did.

 

[lulwut]

Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear

I'm always late to the party :'(

 

[RealiseNothing]

if you did alternate angles from the tangent drawn between the two circles, the proof would be valid right? you're proving that both angles produced from the tangent to their respective lines are equal -> therefore lies on the same line / co-linear.. I think..

I think that's fine.

 

[panda15]

Draw a tangent through the point of intersection, then use angle in alternate segment theorem and vertically opposite angles (angles between the line you are given and your tangent) and prove the two alternate angles are equal therefore must be collinear

I did this. Glad I'm not the only one.

 

[ninasandwich]

yeah... I think I screwed this question up completely- I might scab a mark for it but- I saw I couldn't assume so I forgot about that proof, and instead went with the one that claims "any 3 non-collinear points are con-cyclical points" , then stated as point T is the point of intersection, a line drawn between the centres of the circles passes through T. Therefore since 'Q' and 'P' are points on the circumference of their respective circles, the three points cannot form a circle, and therefore must be collinear. hahah I hope they give me mark for trying

 

[seanieg89]

Was the sneakiest thing ever.

Is there a copy of the paper or question uploaded anywhere?

 

[iBibah]

Is there a copy of the paper or question uploaded anywhere?

Prove Q T and P are collinear.

 

[RealiseNothing]

Hey iBibah, doesn't it remind you of the UNSW seminar back in January.

Where like EVERYONE, including the 3rd year maths students, assumed it was a straight line.

de ja vu

 

[seanieg89]

Hey iBibah, doesn't it remind you of the UNSW seminar back in January.

Where like EVERYONE, including the 3rd year maths students, assumed it was a straight line.

de ja vu

Lol, that's why you should choose usyd .