Resposta :
Resposta:
P(x)=-x^4+3x^3-x^2-4x+1,sendo x=-i
P(-i) =-(-i)⁴ +3 * (-i)³ -(-i)² -4*(-i) + 1
P(-i) =-[(-1)⁴*i⁴] +3 * [(-1)³ *i³] -[(-1)²*i²] -4*(-i) + 1
P(-i) =-i⁴ +3 * (-1) *i³ -i² +4i + 1
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i=√(-1)
i²=[√(-1)]²=-1
i³=i*i²=-i
i⁴=i*i³=i*(-i) =-i²= 1
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