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Matematikaflevering 14/10-05

opg 69: Punktmængde
a X^2 + (5-Y)^2 = 10
(X - 0)^2 + (Y - 5)^2 = 10
C= 0;-5. r= KVROD af 10

b X^2 - 14X + Y^2 + 2Y = -46
(X - 7)^2 + 7^2 + (Y+1)^2 - 1^2 =-46

X^2 - 14X - 7^2 + 7^2 + Y^2 + 2Y + 1^2 - 1^2 = -46
X^2 - 14X + Y^2 + 2Y = -46 - 7^2 + 1^2
X^2 - 14X + Y^2 + 2Y = 4
C= 14;2. r= KVROD af 4

c X^2 +Y2 = Y - X + 15.5
X^2 + X + Y^2 -Y = Y - Y - X + X + 15.5
X^2 + X + Y^2 - Y = 15.5
(X + 0.5)^2 - 0.5^2 + (Y- 0.5)^2 + =.5^2 = 15.5
X^2 + X + 0.5^2 - 0.5^2 ? Y^2 - Y -0.5^2 + 0.5^2 = 15.5
X^2 + X + Y^2 - Y = 15.5 + 0.5^2 - 0.5^2
X^2 - X + Y^2 - Y = 16
C= 1;1. r= KVROD af 16

d X^2 - 6X + Y^2 - Y + 9.25 = 0
(X-3)^2 + 3^2 + (Y-0.5)^2 + 0.5^2 + 9.25 = 0
X^2 - 6X +3^2 - 3^2 + Y^2 - Y + 0.5^2 - 0.5^2 + 9.25 = 0
X^2 - 6X + Y^2 - Y = 0 - 9.25 - 3^2 - 0.5^2
X^2 - 6X + Y^2 - Y = 0
C= 6;-1. r=0