Question

Multiply. (x+4i)(x-4i) Note that these expressions contain comp

Answer 1

To multiply the expressions (x+4i)(x-4i), we can use the FOIL method. FOIL stands for First, Outer, Inner, Last. The result is x^2 + 16.

Step-by-step explanation:

To multiply the expressions (x+4i)(x-4i), we can use the FOIL method. FOIL stands for First, Outer, Inner, Last. We multiply the First terms, then the Outer terms, then the Inner terms, and finally the Last terms. Let's see it step by step:

1. First: x * x = x^2
2. Outer: x *(-4i) = -4ix
3. Inner: 4i * x = 4ix
4. Last: 4i * (-4i) = -16i^2

Combining all these terms, we have x^2 - 16i^2. However, recall that i^2 is equal to -1, so substituting that in, we get x^2 - 16(-1), which simplifies to x^2 + 16.