If x1,x2 are the roots of x2-3x+a=0, and x3,x4 are those of the equationx2-12x++b=0, and x1,x2,x3 and x4 are in increasing G.P.,find a and b.
36I think the question is incomplete.
We must be provided with the common ratio or something like that.....!!
71OK. Proceed like this.
Say, x1 = ∂ , x2 = ∂r , x3 = ∂r2 and x4 = ∂r3
Then from the two equations, we have
∂ (1+r)= 3 and ∂r2 (1+r) = 12
Solving these two by Substitution, we have
r2 = 4
=> r = 2 ....... ( Since this is an increasing GP)
Substitute back in any of the results and get ∂ = 1
Hence the roots are :1,2,4,8.
Therefore, ∂2r = a
=> a = 2
and ∂2r5 = b
=> b = 32
36@vivek - Must say, wonderful soln.
I didn't look at the question that way...!!
71Pehle main tumhe surrender karte dekh daar gaya tha.. Phir solve kiya toh ban gaya!!
