Answer:
10.) -46 -38i
11.) 12 +8i
Explanation:
You want the products (2+6i)(-8+5i) and 4i(2-3i) expressed in standard form.
Expressions with i
An expression containing i can be expanded or simplified by treating i the same as any other variable. All instances of i² can be replaced by -1.
10.
(2 +6i)(-8 +5i) = (2)(-8) +2(5i) +(6i)(-8) +(6i)(5i)
= -16 +10i -48i +30i² . . . . . . i² = -1
= -46 -38i
11.
4i(2 -3i) = (4i)(2) +(4i)(-3i) = 8i -12i²
= 12 +8i . . . . . . . i² = -1