What is the polar form of -2^i?

AI Thread Summary
The discussion revolves around converting -2^i into polar and rectangular forms. Participants clarify the use of logarithmic properties, noting that 2 can be expressed as e raised to a logarithm, specifically 2 = exp(ln(2)). The conversion process involves recognizing that 2^i equals exp(i*ln(2)), leading to its polar form. A key point of confusion arises regarding the interpretation of -2^i, as it can represent either -(2^i) or (-2)^i, which yield different results. Understanding these distinctions is crucial for accurate conversion.
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Homework Statement


Convert -2^i to polar and rectangular form

Homework Equations



mag(a+ib)=sqrt(a^2+b^2)

exp(i*angle)=cos(angle)+i*sin(angle)

The Attempt at a Solution



im not sure how to get the polar (or rectangular form) of -2^i.
i know the answer is exp(-2.448rad)... i just don't know the property that allows me to get there or to the rectangular form
 
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Use the properties of logarithms to convert the 2 into a power of e, ie.
2 = e^{something}
(And yes, I know that 2 is negative. Let's not worry about it right now.)
 
i see wat to do now... thank you... it would be 2=exp(ln2) which means 2^i=exp(ln(2^i))=exp(i*ln(2)) which is polar form... totally forgot the properties of log
 
By -2^i do you mean -(2^i) or (-2)^i. They are different numbers.
 
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