Question

someone help me find all the zeros..... one zeros is -i and another is obviously +i... f(x)=x^4+5x^2+4

Answer 1

since you have \(\pm i\), therefore, you have \(x^2 +1\) is a factor of f(x) , right?
now, use long division to find other 2

Answer 2

i don't know, I did sythetic division and it came out to x^2+4=0 so the other two should be \[\pm2\] but...

Answer 3

the answer is \[\pm 2i\]

Answer 4

\(\pm 2i\) not \(\pm2\)

Answer 5

that is what i dont get how is it 2i