In my calculus class we've just finished working through the two-body problem. We're playing with the conic section equations and on some homework I have to prove that the line tangent to an ellipse makes equal angles with the lines to both foci. I'm having trouble figuring it out. the professor gave a hint that with the ellipse at the origin, the foci at (-a,0) and (a,0), the major axis as (-c,0) and (c,0) and the minor axis from (0,-b) to (0,b), the sum of the distances from both foci to a point will be 2c and a^2+b^2=c^2. I've taken the derivative of the equation for the ellipse to get the slope of the tangent line, but I'm not sure when to go from there. Any hints are appreciated!
tangent to an ellipse proof help!
- Thread starter cjucalc
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