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FP1 modulus-arg form of complex numbers

how do i express the modulus-arg form as x+iy?

for e.g, 5(cos pi/2 + i sin pi/2)

i know that r is 5 and theta is pi/2 but where do i go from here?

thnx
Original post by borborygmus
how do i express the modulus-arg form as x+iy?

for e.g, 5(cos pi/2 + i sin pi/2)

i know that r is 5 and theta is pi/2 but where do i go from here?

thnx


Well, expand, and if possible (in this case it is) evaluate the cos and sine.
Reply 2
Original post by borborygmus
how do i express the modulus-arg form as x+iy?

for e.g, 5(cos pi/2 + i sin pi/2)

i know that r is 5 and theta is pi/2 but where do i go from here?

thnx


Just evaluate the given expression. You know what cosπ/2\cos \pi /2 and sinπ/2\sin \pi /2 are so evaluate them and then multiply the result by five.

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