Question

find the modulus of 2/3-4i

Answer 1

If z = a + ib is any complex number then modulus z = |z| = √(a² + b²)

Given that z = 2/3 - 4i

So modulus of z = | z | = √[(2/3)² + (-4)² ]        [ since a = 2/3  and b = - 4  ]

| z | = √[(4/9)+16]

     = √(4+144)/9

    = √(148/9)

    = 2(√37)/3