Question

Some determine for me the roots
x^4 +6x^2 -27=0

Answer 1

make substitution x^2=y
then the eqn. is (y+9)(y-3)=0 which gives x=+rt(3),-rt(3),3i,-3i

Answer 2

\[x^4+6x^2-27=(x^2+9)(x^2-3)=0\]

Answer 3

are you working with complex numbers or just real? if real the answers are
\[\pm \sqrt{3}\]

Answer 4

real no.s

Answer 5

oops sorry saubhik got it already

Answer 6

oh well in real numbers \[x^2+9=0\] has no solution because if you write \[x^2=-9\] you are looking for a real number whose square is negative and there isn't one.