Question 161207
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{{{x^4-64=0}}}
{{{(x^2-8)(x^2+8)=0}}}--->{{{system(x^2=8,x^2=-8)}}}
{{{x=sqrt(8)}}} ---> Good!
{{{x=sqrt(-8)}}}, don't use
Go back to check:
{{{(sqrt(8))^4-64=0}}} ---> {{{(8^(1/2))^4-64=0}}}
{{{(8^(1/cross(2)))^cross(4)2-64=0}}}
{{{8^2-64=0}}}
{{{64-64=0}}}
{{{0=0}}}
Thank you,
Jojo</pre>