Question

how is (3-i) (3+i)=10

Answer 1

Step-by-step explanation:

(3-i)(3+i)

9 - 3i + 3i -i²

We know that,

(i² = 1)

So,

9 -(-1)

10

Hence Proved

Answer 2

Answer:

10

Step-by-step explanation:

(3-i) (3+i)=10

using formula of a²-b²

=> (3)² - (i)²

=> 9 - (-1)². (putting i² value i.e. (-1)

=> 9 + 1

=> 10

Therefore,

LHS=RHS. Hence Proved