[tex]\it a)\ \ (5-3i) +(2+4i) - (3-2i) = 5-3i+2+4i-3+2i=4+3i\\ \\ b)\ \ (3-4i)(4+5i)=12+15i-16i+20=32-i\\ \\ c)\ \ 4(1-2i)-3(-2+5i)=4-8i+6-15i=10-23i\\ \\ d)\ \ \dfrac{^{3+8i)}4-9i}{\ \ 3-8i}=\dfrac{12-27i+32i+72}{9+64}=\dfrac{84+5i}{73}[/tex]
