2 Simple Questions!

[SGVaibhav]

1) Solve the following inequality :             
|x-2|>1

2) Find the equation of the circle that passes through (0,1) (2,0) (3,4)

[astarmathsandphysics]

When I get up

[SGVaibhav]

u wrote the reply in dreams or while sleeping (sleep writing / sleep posting?)
lool

[astarmathsandphysics]

Yes I was sleep posting

[astarmathsandphysics]

1) Solve the following inequality :             
|x-2|>1

2) Find the equation of the circle that passes through (0,1) (2,0) (3,4)

) Solve
x-2>1 and x-2<-1
x>3 or x<1
2)The equation of a circle is given by

Sub each point in and solve the simultaneous equations
(1)
(2)
(3)
(2)-(1) 3+2a-b=0 (4)
(3)-(1)24+3a+3c=0 so 8+a+b=0 (5)
(4)+(5) 11+3a=0 so a=-3/11
then from (5)8-3/11+b=0 so b=-85/3
Then from (1) 1-85/3+c=0 so c=82 over 3
x^2+y^2-3x/11-85y/3+82/3=0

[SGVaibhav]

understood everything EXCEPT, what do u do after finding a, b and c in the 2nd question.

[astarmathsandphysics]

sub them into th e formula for the circle x^2+y^2+ax+by=c

[SGVaibhav]

so how do we then get the center and radius, i forgot

[astarmathsandphysics]

Complete the square. Will do it proper when I get home

[SGVaibhav]

oh yeah, i found out something...

i got another method, it says Centre = (-A/2  , -B/2)    (i dont know if its right)
                                    and radius = Square root of ( (-a/2)^2  +   (-b/2)^2   - c))     [square root of   -a/2 square + -b/2 square - c]

[astarmathsandphysics]

Yes that is true