SOLUTION: find all the zeros and state any multiplicity: j(x)=x^4+7x^2-18 k(x)=15x^3-60x^2+2x-8

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Question 856449: find all the zeros and state any multiplicity:
j(x)=x^4+7x^2-18
k(x)=15x^3-60x^2+2x-8
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
find all the zeros and state any multiplicity:
j(x)=x^4+7x^2-18
x^4+7x^2-18=0
(x^2+9)(x^2-2)=0
..
x^2+9=0
x^2=-9
x=±√-9
x=±3i
..
x^2-2=0
x=±√2
2 real and 2 non-real zeros
...
k(x)=15x^3-60x^2+2x-8
15x^3-60x^2+2x-8=0
15x^2(x-4)+2(x-4)=0
(x-4)(15x^2+2)=0
..
x-4=0
x=4
..
15x^2+2=0
x^2=-2/15
x=±√(-2/15)
x=±√(2/15)i
1 real and 2 non-real zeros