हिंदी

Ellipse and its Types

Advertisements

Topics

Estimated time: 5 minutes
Maharashtra State Board: Class 12

Definition: Ellipse

An ellipse is the set of all points in a plane, the sum of whose distances from two fixed points in the plane is constant.

Maharashtra State Board: Class 12

Key Points: Ellipse and its Types

Fundamental Terms Horizontal Ellipse (a>b) Vertical Ellipse (a<b)
Equation \[\frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}}=1\] \[\frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}}=1\]
Centre (0,0) (0,0)
Vertices (±a,0) (0,±b)
Length of major axis 2a 2b
Length of minor axis 2b 2a
Foci (±ae,0) (0, ±be)
Relation between (a,b,e) \[\mathrm{b}^{2}=\mathrm{a}^{2}(1-\mathrm{e}^{2})\] \[\mathbf{a}^{2}=\mathbf{b}^{2}(1-\mathbf{e}^{2})\]
Eccentricity \[\mathrm{e}=\frac{\sqrt{\mathrm{a}^{2}-\mathrm{b}^{2}}}{\mathrm{a}}\] \[\mathrm{e}=\frac{\sqrt{\mathrm{b}^{2}-\mathrm{a}^{2}}}{\mathrm{b}}\]
Equation of directrices \[x=\pm\frac{\mathrm{a}}{\mathrm{e}}\] \[y=\pm\frac{b}{e}\]
Distance between foci 2ae 2be
Distance between directrices \[\frac{2a}{e}\] \[\frac{2b}{e}\]
Length of latus rectum \[\frac{2\mathrm{b}^2}{a}\] \[\frac{2\mathrm{a}^2}{b}\]
Endpoints of the latus rectum \[\left(\pm ae,\pm\frac{b^{2}}{a}\right)\] \[\left(\pm\frac{a^{2}}{b},\pm be\right)\]
Equation of axes Major: (y = 0), Minor: (x = 0) Major: (x = 0), Minor: (y = 0)
Parametric equations \[\begin{cases} x=a\cos\alpha \\ y=b\sin\alpha & \end{cases}\] \[\begin{cases} x=a\cos\alpha \\ y=b\sin\alpha & \end{cases}\]
Focal distances \[\mid SP\mid=\left(a-ex_{1}\right)\mathrm{and}\mid S^{\prime}P\mid=\left(a+ex_{1}\right)\] \[\mid SP\mid=(b-ey_{1})\mathrm{~and}\mid S^{\prime}P\mid=(b+ey_{1})\]
Sum of focal radii 2a 2b
Equation of the tangent at the vertex (x = ± a) (y = ± b)

Shaalaa.com | Standard equations of an ellips

Shaalaa.com


Next video


Shaalaa.com


Standard equations of an ellips [00:03:01]
S
Series:
0%


Advertisements
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×