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1 vote
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Evaluate y=x^2+x-4, given x=2i

User Ji Sungbin
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1 Answer

18 votes
18 votes

Answer:

y = - 8 + 2i

Explanation:

Substitute x = 2i into the equation, noting i² = - 1

y = (2i)² + 2i - 4

= 4i² + 2i - 4

= 4(- 1) + 2i - 4

= - 4 + 2i - 4

= - 8 + 2i

User Chris Judge
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