Question

(13 + i)(13 - i) simplify the expression

Answer 1

`{ \tt{(13 + i)(13 - i)}}`

From difference of two squares identity;

`{ \tt{(a + b)(a - b) = ( {a}^(2) - {b}^(2) ) }}`

Therefore; Consider

• a = 13
• b = i

`= { \tt{( {13}^(2) - {i}^(2) )}} \\ \\ = { \tt{169 - ( - 1)}} \\ \\ = 170`