If z₁ = (2 – i) and z₂ = (1 + i), find .

Given: z₁ = (2 – i) and z₂ = (1 + i)

To find:

Consider,

Putting the value of z₁ and z₂, we get

Now, rationalizing by multiply and divide by the conjugate of 1 – i

[(a – b)(a + b) = a² – b²]

[Putting i² = -1]

= |2(1 + i)|

= |2 + 2i|

Now, we have to find the modulus of (2 + 2i)

So,