<s>[INST] Solve the equation $x^7- 2ix^4 - ix^3 -2 = 0$ for $x$ I am having difficulty factorising the equation. 
 [/INST] $$x^7-ix^3-2ix^4-2=0\\(x^7-ix^3)-2(ix^4+1)=0\\
x^3(x^4-i)-2(ix^4+1)=0\\\frac{i}{i}x^3(x^4-i)-2(ix^4+1)=0\\
\frac{1}{i}x^3(ix^4-i^2)-2(ix^4+1)=0\\
\frac{1}{i}x^3(ix^4+1)-2(ix^4+1)=0\\ 
(\frac{x^3}{i}-2)(ix^4+1)=0\\
(\frac{x^3-2i}{i})(ix^4+1)=0\\ \to
(x^3-2i)(ix^4+1)=0\\$$
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