Question

What's the value of the product (3-2i)(3+2i)

Answer 1

(3 - 2i)(3 + 2i) . Its form is (a - b)(a + b) = a² - b²
( a = 3 and b = 2i)

(3)² - (2i)²
= 9 - (4i²) , but 1² = -1
= 9 - (-4) = 9+4 = 13

So (3-2i)(3+2i) = 13