Find the product of 4 + i and 4 – i.

Answer 1

To find the product of (4 + i) and (4 – i), we can use the FOIL method, which stands for First, Outer, Inner, Last.

(4 + i) * (4 – i) = 4 * 4 + 4 * (-i) + i * 4 + i * (-i)

= 16 - 4i + 4i - i^2

= 16 - i^2

Since i^2 = -1, we can substitute it in the above equation:

= 16 - (-1)

= 16 + 1

= 17

Therefore, the product of (4 + i) and (4 – i) is 17.