How to understand WolframAlpha(limits) answer?

Question

Mathematics

I solved one example here, I decided to check it through wolfram alpha and fell into a misunderstanding. Please explain.
My solution and initial condition

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Tungsten solution:

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Thanks in advance for your reply!

Answer 1

I haven't looked at Wolfram's solution, but (-8)^2 is not 16, but 64. Perhaps there are more errors.
UPD. Looked. They take as (-8)^(1/3) not -2, but 2*exp(i*pi/3)=1+i*sqrt(3). Theoretically, they have the right, although this is not what is needed in the matan problem.