Question
Mon May 14, 2012 By:

# Proving type

Expert Reply
Sat May 19, 2012
the equation in quadratic can be written as
a(x+2)4 + b(x+2)2 + c = 0

Let (x+2)2 = t , So the equation becomes

at2 + bt + c = 0

Now since b2 - 4ac > 0 , thus D > 0

Now t = {-b +- root(D) }/2a

Also t = (x+2)2 , thus t cannot be negative ,

Now ,
CASE 1 :
If b>0 , then b must be greater than both a , c , also a and c must be negative which proves the first statement .

CASE 2 :
If b < 0 , then a , c must be positive and greater than 0 to give positive value of t where either  a and c can be greater which proves 2nd and 3rd statments .
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# TO TOPPER LEARNING TEAM - Is there any expert in topper learning team who can reply my queries with proper logic else regret the same. Plz also arrange to remove wrong reply of experts against my questions raised. THIS REFERS TO SOLUTION PROVIDED BY YOU OF ATTACHED QUESTION. YOUR EXPERT SNEHA HAS MENTIONED THAT (X+1)(X^2+X+1)= X^3+2X^2+2X+1=0 HAS ROOT -1 AND IT IS ALWAYS -d/a. MY QUESTION IS WHY IT IS NOT (a-b)/a. PLEASE REPLY WITH PROPER LOGIC.

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