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A complex number is given by z=(1+2i)/(...

A complex number is given by `z=(1+2i)/(1-(1-i)^(2))`
What is the modulus of z ?

A

4

B

2

C

1

D

`1/2`

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AI Generated Solution

The correct Answer is:
To find the modulus of the complex number \( z = \frac{1 + 2i}{1 - (1 - i)^2} \), we will follow these steps: ### Step 1: Simplify the denominator We need to simplify \( 1 - (1 - i)^2 \). 1. Calculate \( (1 - i)^2 \): \[ (1 - i)^2 = 1^2 - 2 \cdot 1 \cdot i + i^2 = 1 - 2i - 1 = -2i \] 2. Substitute this back into the expression for \( z \): \[ 1 - (1 - i)^2 = 1 - (-2i) = 1 + 2i \] ### Step 2: Rewrite \( z \) Now we can rewrite \( z \): \[ z = \frac{1 + 2i}{1 + 2i} \] ### Step 3: Simplify \( z \) Since the numerator and denominator are the same: \[ z = 1 \] ### Step 4: Find the modulus of \( z \) The modulus of a complex number \( z = a + bi \) is given by: \[ |z| = \sqrt{a^2 + b^2} \] In our case, \( z = 1 + 0i \), so \( a = 1 \) and \( b = 0 \): \[ |z| = \sqrt{1^2 + 0^2} = \sqrt{1} = 1 \] ### Final Answer The modulus of \( z \) is \( 1 \). ---

To find the modulus of the complex number \( z = \frac{1 + 2i}{1 - (1 - i)^2} \), we will follow these steps: ### Step 1: Simplify the denominator We need to simplify \( 1 - (1 - i)^2 \). 1. Calculate \( (1 - i)^2 \): \[ (1 - i)^2 = 1^2 - 2 \cdot 1 \cdot i + i^2 = 1 - 2i - 1 = -2i ...
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