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How to do
Maths problem: how to fo, thanks?
回答 (1)
2020-05-02 8:13 pm
✔ 最佳答案
(a)C₂ : 4x + 6y -x² -y² = -23
x²-4x +y²-6y = 23
(x-2)²-4 +(y-3)²-9 = 23
(x-2)² + (y-3)² = 36
(x-2)² + (y-3)² = 6²
∴ centre of C₂ = (2,3)
∴ centres of C₁,C₂ are the same
(b) radius of C₂ = 6
=> radius of C₁ = 3
So, eqt. of C₁ :
(x-2)² + (y-3)² = 3²
x²-4x+4 +y²-6y+9 = 9
x²+y²-4x-6y+4 = 0 (general form)
收錄日期: 2021-04-24 07:49:14
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20200502112539AAZaqUs