In Q. No 126, `c=` (a) `b` (b) `2b` (c) `2b^2` (d) `-2b`

If acottheta+b"c o s e c"theta=p and bcottheta+a"c o s e c"theta=q , then p^2-q^2= (a) a^2-b^2 (b) b^2-a^2 (c) a^2+b^2 (d) b-a

If a ,\ b ,\ c are in proportion, then (a) a^2=b c (b) b^2=a c (c) c^2=a b (d) None of these

If D is the mid-point of the side B C of triangle A B C and A D is perpendicular to A C , then (a) 3b^2=a^2-c (b) 3a^2=b^2 3c^2 b^2=a^2-c^2 (d) a^2+b^2=5c^2

If D is the mid-point of the side B C of triangle A B C and A D is perpendicular to A C , then 3b^2=a^2-c ^2 (b) 3a^2=b^2 3c^2 b^2=a^2-c^2 (d) a^2+b^2=5c^2

If D is the mid-point of the side B C of triangle A B C and A D is perpendicular to A C , then 3b^2=a^2-c ^2 (b) 3a^2=b^2 3c^2 b^2=a^2-c^2 (d) a^2+b^2=5c^2

If a ,b,c , d are in G.P. prove that (a-d)^(2) = (b -c)^(2)+(c-a)^(2) + (d-b)^(2)

If D is the mid-point of the side B C of triangle A B C and A D is perpendicular to A C , then 3b^2=a^2-c (b) 3a^2=b^2 3c^2 b^2=a^2-c^2 (d) a^2+b^2=5c^2

If the roots of the equation (a^2+b^2)x^2-2b(a+c)x+(b^2+c^2)=0 are equal, then (a) 2b=a+c (b) b^2=a c (c) b=(2a c)/(a+c) (d) b=a c

If (a+b+2c+3d)(a-b-2c+3d)=(a-b+2c-3d)(a+b-2c-3d) , then 2b c is equal to 3/2 (b) (3a)/(2d) (c) 3a d (d) a^2d^2

If a, b, c and d are in G.P., show that, (b-c)^(2) + (c-a)^(2)+ (d-b)^(2) = (a-d)^(2) .