1.the real value of 'c' so that an tangent from a point on x^{2}+y^{2}+10x-8y +c^{2}-32 to x^{2}+y^{2}+10x-8y +2c^{2}-41=0 of length √40.
a.25 b.5 c.4 d.does not exist.
2.AB is a focal cord of y^{2}=4ax with the point A corresponding to t=2.then[\Delta]i.e the area enclosed by the normal at B with the co-ordinate axis and [.]representing greatest integer function is a.0 .1 c.2 .4
3.the vertex V of the parabola with focus at(-1,-1) and directrix 3x-4y+9=0 lies on the line
a.x+8y=0 b.8x-y=0 c.x-8y=0 d.8x+y=0
i m getting 3-a and 2-b...are they right????????
1Q 1 .. see the circles are concentric... centre is -5,4....find r1 and r2 (let r2>r1) take a point on the larger circle say (-5,4+r2)...now length of tangent from a xternal point (x1,y1) on the circle is √S1..use it....I gave u the method ..now u should solve it!!
1Q3) the line through the vertex and the focus is perpendicular to the directrix
1Well ur 2nd ques is a simple 1.......
L1 -- 3x-4y+9=0 .... say
find L2 perp to L1 passin thru (-1,-1)
nxt find intersection pt of L1 & L2...
& finally solve 4 d mid pt of (-1,-1) & the found out pt.....
