yes it is correct
if A and B are the roots of x2-8x+4M=0 and C and D x2-72X+4N=0 if A<B<C<d and A,B,C,D are in GP then MN=
A)729/4
B)27/16
C)729
D)243
-
UP 0 DOWN 0 0 3
3 Answers
Lokesh Verma
·2009-03-16 04:22:31
AB=4M
A+B=8
C+D=72 = r2(A+B)
CD=4N = r4AB
thus, 72=r2.8
r=3
A+Ar=8
thus, A=2
B=6, C=18, D=54
ABCD= ?