Author Topic: maths C2 doubt  (Read 912 times)

Offline halosh92

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maths C2 doubt
« on: February 19, 2010, 11:40:48 am »
The points R(-2,5) S(2,1) T(-6,1) lie on the circumference of a circle. Find the equation of
RS and RT and hence find the coordinate of the centre of the circle
?????
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Offline astarmathsandphysics

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Re: maths C2 doubt
« Reply #1 on: February 19, 2010, 12:03:22 pm »

Offline halosh92

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Re: maths C2 doubt
« Reply #2 on: February 19, 2010, 01:40:41 pm »
Method shown here

https://studentforums.biz/index.php/topic,5560.0.html

there is the method of the perpendicular bisector method could you explain it perpendicular bisector wise?
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline astarmathsandphysics

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Re: maths C2 doubt
« Reply #3 on: February 19, 2010, 01:51:50 pm »
Sorry saw three points and thought simultaneous eqs. When I get home

Offline astarmathsandphysics

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Re: maths C2 doubt
« Reply #4 on: February 19, 2010, 05:31:07 pm »
R(-2,5) S(2,1) T(-6,1)
RS gradient =(1-5)/(2--2)=-1
Y=-X+C
5==--2+c c=3
Y=-X+3
RT gradient =(1-5)/(-6--2)=1
y=x+c
5=-2+c c=7
y=x+7

Offline astarmathsandphysics

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Re: maths C2 doubt
« Reply #5 on: February 19, 2010, 05:35:15 pm »
Hence lines are at right angles with the right angle at R

hence St is a diamter
ST=sqrt((-6-2)^2+(1-1)^2)=8
radius =8/2=4
centre at(S+T)/2=((2,1)+(-6,1))/2=(-2,1)

Offline halosh92

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Re: maths C2 doubt
« Reply #6 on: February 19, 2010, 06:20:14 pm »
Hence lines are at right angles with the right angle at R

hence St is a diamter
ST=sqrt((-6-2)^2+(1-1)^2)=8
radius =8/2=4
centre at(S+T)/2=((2,1)+(-6,1))/2=(-2,1)

thx alot! :D
everyday we wake up is a miracle, then how do we say miracles dont happen?????