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can you please tell me what i did wrong?

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Hi Daisy,
g(x)=x^3-125/x^2+1
      =(x-5)(x^2+5x+25)
now we can find complex roots for (x^2+5x+25),
 
x^2+5x+25=0
using formula,if ax^2+bx+c=0,
then x= -b ±√b²-4ac ⁄ 2a
substituting a= 1, b= 5, c= 25, we get,
 
x= -5±√5²-4(1)(25)/ 2(1)
  =-5 ±√25-100/2
  =-5 ± √-75 /2.............(√-75=√25*3*-1=5√3 i  as √-1=i)
x= -5+5√3 i /2  or x= -5-5√3 i /2
 
Denominator cannot be equal to zero.
 
Ans: zeros are 5, -5+5√3 i/2, -5-5√3 i /2
 
Meena from Strongsville,OH

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