a- the common tangent to the circle x2+y2=6xand x2+y2+2x=0 forms an........... triangle

b-if 2 distinct chords of circle x2+y2=ax+by r drawn from pt a,b are divided by the x axis in 2;1 find relation b/w a and b

c- find eqn of locus of feet of perpendicular drawn from origin upon a variable chord of a circle which subtend right angle at origin

1)



x2+ y2 = 6x  (1) and x2 + y2+ 2x = 0  (2)
So the centre of the circle (1) is (x-3)2 +(y-0)2  = 9 is (3 ,0) and radius = 3
And centre of the circle (2) is (x +1)2 + (y-0)2 = 1  is ( -1 ,0) and radius = 1

C1B + BC2  = 4 ,
1 + 3 = 4
Hence the circle touches each other externally.
We can find the coordinate of A by using the external division
So A (x1 ,y1)  can be found as :
x1 =3(-1) - 1(3)3-1  = -3 and  y1  =3(0)-1(0)3-1 = 0

And B(x2 ,y2)  by internal division .
x2 =3(-1) +1(3)3+1 =0 and y2 = 0
So AB = 3
And AP = AQ  =  AT1 +AT22 = 22-12+62-322 =23
And PB  = AP2-AB2 =12-9 =3
So PQ = 2(31/2 )

So all three sides are equal , hence the triangle formed is equilateral.




 

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