Question

dados z1=2+3i e z2=2-5i,resolva

a)z1.z2
b)z1-z2


por favor me AJUDEM............

Answer 1

Boa noite Jhonatan!

Solução!


Não esqueça!  $i^{2}=-1$


$Z_{1}=(2+3i)\\\\ Z_{2}=(2-5i)$



$A) \\\\ Z_{1} \times Z_{2}\\\\ (2+3i) \times(2+5i)\\\\ (4-10i+6i-15i^{2})\\\\ (4-4i-15(-1))\\\\ (4-4i+15)\\\\ (4+15-4i)\\\\ (19-4i)$



$B)\\\\ Z_{1}=(2+3i)\\\\ Z_{2}=(2-5i)\\\\\\ Z_{1}-Z_{2}\\\\ ((2+3i)-(2-5i)) \\\\\ ((2+3i)+(-2+5i))\\\\ (2-2+3i+5i)\\\\ (0+8i)\\\\ 8i$


$\boxed{Resposta: A=(19-4i)~~B=(8i)}$


Boa noite!

Bons estudos!