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Find the eccentricity, one of the foci, thedirectrix, and the length of the latus rectum for the conic `(3x-12)^2+(3y+15)^2=((3x-4y+5)^2)/(25)`. |
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Answer» Correct Answer - e= 1/3; focus `-=` (4,5); directrix : 3x-yy+5=0; L.R.=2/5 `(3x-12)^(2)+(3y+15)^(2)=((3x+4y+5)^(2))/(25)` or `sqrt((x-4)^(2)+(y+5)^(2))=(1)/(3)(|3x-4y+5|)/(5)` Hence the ratio of distance of he variable point P(x,y) from the foxed point (focus) (4,5) to that from the fixed line (directrix`-=3x-4y+5=0)` is 1/3 Also, the locus is an ellipse and its eccentricity is 1/3 Alos, lenght of the latus reactum `=2(e)xx` (Distance of (4,5) from the line 3x-4y+5=0 `=2xx(1)/(3)(|3xx4-4xx5+5|)/(5)=(2)/(5)` |
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