Multiply the binomials:

(5 + 2i)(5-2i)

1 answer

To multiply the binomials \((5 + 2i)(5 - 2i)\), we can use the formula for the difference of squares, which states that \((a + b)(a - b) = a^2 - b^2\).

In this case, let:

  • \(a = 5\)
  • \(b = 2i\)

Using the difference of squares, we can find:

\[ (5 + 2i)(5 - 2i) = 5^2 - (2i)^2 \]

Calculating each term:

  1. \(5^2 = 25\)
  2. \((2i)^2 = 4i^2\)

Since \(i^2 = -1\), we have:

\[ 4i^2 = 4(-1) = -4 \]

Now substituting this back into the expression:

\[ (5 + 2i)(5 - 2i) = 25 - (-4) = 25 + 4 = 29 \]

Thus, the result of multiplying the binomials \((5 + 2i)(5 - 2i)\) is:

\[ \boxed{29} \]