Linked Questions

2 votes
2 answers
2k views

Orthogonal tangents to an ellipse [duplicate]

This is the problem I found back in the first year in the university. Suppose we have a non-degenerate (i.e. not a point and not an empty set) ellipse $E\subset \Bbb R^2$. Now define a set $D$ by a ...
TZakrevskiy's user avatar
  • 23.1k
0 votes
0 answers
330 views

Given an ellipse, find the equation of the set of all points from which there are two tangents to the curve whose slopes are reciprocal. [duplicate]

Given an ellipse $x^2/a^2+y^2/b^2=1,$ where $a\not=b,$ find the equation of the set of all points from which there are two tangents to the curve whose slopes are (a) reciprocals and (b) negative ...
larry's user avatar
  • 19
0 votes
1 answer
47 views

Finding formula of all solution of a point P, where two tangent line to an ellipse from P is perpendicular to each other [duplicate]

the only information given is ellipse equation x^2/17+y^2/8=1, first I tried to substitute y in ellipse equation with m(x-a)+b, then I tried to make determinant zero, getting 2nd order equation of am^...
AegisNine's user avatar
14 votes
3 answers
16k views

How to get the limits of rotated ellipse?

The box that an ellipse fits is easily calculated if there are no rotation, or if the rotation is ${x*90^o}$ (where x is an integer) is easy. For a (major radius) and b (minor radius), it is : <...
BЈовић's user avatar
2 votes
4 answers
3k views

How to calculate width and height of a 45° rotated ellipse bounded by a square?

I'm coming from a programming background so I apologies if this is blindingly simple or I misuse terms. I have an ellipse bounded by a square. For simplicity the centre of the square and ellipse is ...
AnnanFay's user avatar
  • 510
1 vote
3 answers
4k views

Finding the locus of a point $P$ if the tangents drawn from $P$ to circle $x^2 + y^2 = a^2$ so that the tangents are perpendicular to each other?

Question: Find the locus of a point $P$ if the tangents drawn from $P$ to circle $x^2 + y^2 = a^2$ so that the tangents are perpendicular to each other. I tried solving this and then I got to this ...
dada wilson's user avatar
4 votes
1 answer
1k views

Rectangle circumscribed to an ellipse of max area/perimeter

I could solve the classical problem of maximizing the area (fixing the perimeter) or maximizing the perimeter (fixing the area) of an inscribed rectangle, but I don't know how to solve ...
mathlearner's user avatar
1 vote
2 answers
2k views

Relation of ellipse semi-axes with rotation angle and projection length

In the following setup, assume $w$ (length of the projection of the ellipse) and $\theta$ (the rotation angle) are known. I want to know what equation(s) do I have here that helps me to derive the ...
Ragowa's user avatar
  • 11
6 votes
3 answers
353 views

Can a figure inside a circle be seen at right angle from any point on the circle?

A convex, closed figure lies inside a given circle. The figure is seen from every point of the circumference at a right angle (that is, the two rays drawn from the point and supporting the convex ...
user19405892's user avatar
  • 15.6k
2 votes
0 answers
736 views

Find the number of points on ellipse $\frac{x^2}{50}+\frac{y^2}{20}=1$ from which pair of perpendicular...

Find the number of points on ellipse $\frac{x^2}{50}+\frac{y^2}{20}=1$ from which pair of perpendicular tangents are drawn to ellipse $\frac{x^2}{16}+\frac{y^2}{9}=1$ Normal from a point $(5\sqrt{2}...
Sachin's user avatar
  • 10k
0 votes
0 answers
107 views

how to obtain peripheral recangle of arbitrary ellipse?

Suppose have arbitrary ellipse with center $(x,y)$ and its radius $(a,b)$. I want obtain rectangle that sides tangent of peripheral ellipse. the below image describe issue :
ali kiani's user avatar
  • 101
0 votes
1 answer
80 views

Set of points from which tangent lines to given hyperbola are perpendicular.

Find set of points from which start two perpendicular tangent lines to hyperbola $$\frac{x^2}{a^2}-\frac{y^2}{b^2}=1$$ Tangent lines to a hyperbola are $y=mx+\sqrt{a^2m^2-b^2}$ and $y=mx-\sqrt{a^2m^2-...
eremite's user avatar
  • 137
0 votes
1 answer
56 views

$\alpha$-isoptic curve of a conic section

Could someone tell me where I can find the generic equation of the $\alpha$-isoptic of a conic section of this form: $$\Gamma: ax^2+2bxy+cy^2+2dx+2ey+f=0$$ I searched in many links and PDFs but I ...
Math Attack's user avatar