Mathematics A-Level
centre and radius
What centre and radius means in Mathematics A-Level, as defined for WJEC.
Definition of centre and radius
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Reference: WJEC
Found by completing the square separately on x and y, giving centre (−g, −f) and radius r = √(g² + f² − c).
Topics that use centre and radius
Related terms
- angle in a semicircle
- linear modelling
- perpendicular bisector of chord
- point-slope form
- rate of change
- tangents and normals
- circle equation
- completing the square for circles
Using centre and radius in the exam
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