Answer
(a) $u+v=-3i-4j$
(b) $u-v=-11i-2j$
(c) $4u=-28i-12j$
(d) $3v+5u=-23i-18j$
Work Step by Step
(a) $u+v=(-7i-3j)+(4i-j)=(-7+4)i+[-3+(-1)]j=-3i-4j$
(b) $u-v=(-7i-3j)-(4i-j)=(-7-4)i+[-3-(-1)]j=-11i-2j$
(c) $4u=4(-7i-3j)=4(-7i)+4(-3j)=-28i-12j$
(d) $3v+5u=3(4i-j)+5(-7i-3j)=3(4i)+3(-j)+5(-7i)+5(-3j)=12i-3j-35i-15j=-23i-18j$
