Question 1180205: What are the possible number of positive, negative and imaginary zeros of:
f(x)= x^3 - 11x^2 + 8x - 20
Answer by MathLover1(20850)   (Show Source):
You can put this solution on YOUR website!
Use Decartes' rule of signs...
So, the coefficients are  , , ,
As can be seen, there are  changes.
This means that there are or  positive real roots.
To find the number of negative real roots, substitute  with  in the given polynomial:
 becomes 
The coefficients are  ,, ,.
As can be seen, there are changes.
This means that there are negative real roots.
Answer:
 or positive real zeros
 negative real zeros
or  imaginary zeros
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