a, b, c are the first three terms of geometric series. If the H.M. of a and b is 12 and that of b and c is 36 then which of the following hold(s) good?

a, b, c are the first three terms of a geometrical series. If the harmonic mean of a and b is 12 and that of b and c is 36, find the first five terms of series.

If b+c+,c+a,a+b are in H.P. then which of the following hold(s) good ?

If b+c+,c+a,a+b are in H.P. then which of the following hold(s) good ?

If a ,b ,c are first three terms of a G.P. If the harmonic mean of a and b is 20 and arithmetic mean of b and c is 5, then

If a,b,c,d,e are positive numbers, then which of the following holds good

In Delta ABC, if b=sqrt(3),c=1 and A=30^(@) then which of the following hold good?

In a triangle ABC, let 2a^2+4b^2+ c^2= 2a(2b + c) , then which of the following holds good?