polar form of complex numbers

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section 9-6 polar form of complex numbers
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rectangular form xyipolar form
r(cos?isin?) ? -amplitude r
-magnitude
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write 1-4i in polar form
rv((12)(-4)2) v17
? Arctan(-4/1) -1.33 or
-1.332p4.95 get a pos. angle
v17(cos4.95isin4.95)
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Example -3-2i
rv((-32)(-2)2) v13
? Arctan(-2/-3) p .5883.14
3.73
v13(cos3.73isin3.73)
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example. 1i
rv(1212) v2
? Arctan(1/1) p/4
v2(cos(p/4)isin(p/4)) some values can be
found on the unit circle. If so, use EXACT values.
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if you know r ?, express in rectangular form
? 150 and r 2
2(cos150isin150)
a 2cos150 -v3 b 2sin150 1
(-v3,1) or -v3i
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p.504 15-31odd,34,39