Question

Sendo z = 5i + 3i2 - 2i3 + 4i27 e w = 2i12 - 3i15 ,
calcule Im(z).w + Im(w).z .

O resultado tem que dar: -3 + 18i

Answer 1

z = 5i + 3i2 - 2i3 + 4i27 e w = 2i12 - 3i15 ,  calcule Im(z).w + Im(w).z . 

i27 = i3 ==> - i    ;    i12 = i0 ==> 1   ;  i15 = i3 ==> - i
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z = 5i + 3i2 - 2i3 + 4i27 ==> 5i +3(-1) - 2(-i) + 4(-i) 

z = 5i - 3 + 2i - 4i ==> z = - 3 + 3i
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w = 2i12 - 3i15 ==> 2i^0 - 3(-i) ==> 2.1 + 3i ==> w = 2 + 3i
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Im(z).w + Im(w).z . 

3(2+3i) + 3(- 3 +3i) ==> 6 + 9i - 9 + 9i ==> - 3 + 18i ou  3( - 1 + 6i )