Hi,

consider:

an ellipse formed by the locus of a point whose distances from the point (4,3) and the point (4,7) always add up to 14.

Find the equation of the ellipse...

Thank you

How can you covert the following Polar equation in to its Cartesian version,

$r=a/(1+\cos \theta )$, where $a$ is constant, $-\pi /2<\theta <\pi /2$
Can you do sketch of it when the parabola is in its polar form or do you have to put it into the cartesian form?

Thanks.

For the first question, we can work out the semi-major and semi-minor axes, thus obtain the equation, since the centre is at (4,5).

For the second question, use the equations cos q =x/r, and r² =x² +y² to convert the polar equation to Cartesian form.

For the final question, one can always do sketches when one knows what to sketch.

Kerwin

thanks.

Kerwin,

you could also find the foci of the ellipse...

From there, work your way through using standard results!