Question

Alguém poderia me ajudar com esses exercícios? Porfavor!!!!

Answer 1

Resposta:

1) A; 2) B; 3) C; 4) D

Explicação passo-a-passo:

1) $A=2+3i$, $B=5-i$, $C=-3+4i$

Queremos $2A+B-C$

$2A+B-C=2\cdot(2+3i)+5-i-(-3+4i)$

$2A+B-C=4+6i+5-i+3-4i$

$2A+B-C=12+i$

2) Agora vamos calcular $A\cdot B$

$A\cdot B=(2+3i)\cdot(5-i)$

$A\cdot B=10-2i+15i-3i^2$

$A\cdot B=10+3+15i-2i$

$A\cdot B=13+13i$

3) Utilizando Briot-Ruffini:

$.~~~~|~~~~~2~~~|~~-3~~~~~|~~~~~3~~~~~~|~~~~~-5$

$2~~~~|~~~2~~~~|~~~~~~1~~~~~~|~~~~~5~~~~~~|~~~~~5$

O resto é $5$

4) O quociente vale $2x^2+x+5$