If a,b,c are in H.P and ab + bc ca = 15, then ca =

If a+b+ c=9 and ab + bc +ca = 15 , find : a^2 + b^2 + c^2 .

If a,b,c are in A .P and a^(2),b^(2),c^(2) are in H.P ,then b^(2) = (A) (ca)/(2) (B) 2ca (C) -(ca)/(2) (D) -2ca

If a,b,c are in A.P then a+1/(bc), b+1/(ca), c+1/(ab) are in

Q.If a,b,c are in AP,then bc,ca,ab are in ?

If a, b, c are in A.P., then prove that : (i) b+c,c+a,a+b" are also in A.P." (ii) (1)/(bc),(1)/(ca),(1)/(ab)" are also in A.P." (iii) (a(b+c))/(bc),(b(c+a))/(ca),(c(a+b))/(ab)" are also in A.P."

If a + b+ c= p and ab + bc + ca= q , find a^(2) +b^(2) + c^(2)