The Circle — Chapter Summary
ICSE · Class 11 · Mathematics
Summary of The Circle for ICSE Class 11 Mathematics. Key concepts: A circle is the locus, The standard equation is (x and The general equation is.
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Overview
A circle is the locus of all points in a plane that are equidistant from a fixed point. The fixed point is called the centre, and the common distance is called the radius. The chapter builds a complete study of circles through their standard, general, diameter, and parametric equations, and also exp
Key Concepts
A circle is the locus
A circle is the locus of all points in a plane equidistant from a fixed point. The fixed point is the centre, the distance from the centre to any poin
The standard equation is (x
The standard equation is (x-h)^2+(y-k)^2=r^2, where (h,k) is the centre and r is the radius. For a circle with centre at the origin, the equation beco
The general equation is x^2+y^2+2gx+2fy+c=0
The general equation is x^2+y^2+2gx+2fy+c=0. It represents a circle with centre (-g,-f) and radius sqrt(g^2+f^2-c). The coefficients of x^2 and y^2 mu
If the end
If the end-points of a diameter are (x1,y1) and (x2,y2), then the circle is given by (x-x1)(x-x2)+(y-y1)(y-y2)=0. The result comes from the fact that
A circle with centre (h
A circle with centre (h,k) and radius r can be written as x=h+r cosθ and y=k+r sinθ, where 0≤θ<2π. As θ varies from 0 to 2π, the point traces the whol
Learning Objectives
- Define a circle and identify its centre, radius, chord, and diameter.
- Write the standard equation of a circle and use it to find centre and radius.
- Recognise and use the general equation of a circle.
- Find the equation of a circle from diameter end-points.
- Write a circle in parametric form and convert between parametric and Cartesian forms.
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