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For any two complex numbers z(1) and z(2...

For any two complex numbers `z_(1)` and `z_(2)`
`|z_(1)+z_(2)|^(2) =(|z_(1)|^(2)+|z_(2)|^(2))`

A

Statement-1 is True, Statement-2 is True: Statement-2 is a correct exp,anation for statement-1.

B

Statement-1 is true, statement -2 is true, Statement-2 is not a correct explanation for statement-1.

C

Statement-1 is True, statement-2 is false,

D

statement-1 is False, Statement-2 is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to prove that for any two complex numbers \( z_1 \) and \( z_2 \), the equation \[ |z_1 + z_2|^2 = |z_1|^2 + |z_2|^2 \] holds true under certain conditions. Let's go through the steps to derive the solution. ### Step 1: Start with the left-hand side We begin with the left-hand side of the equation: \[ |z_1 + z_2|^2 \] Using the property of modulus, we can express this as: \[ |z_1 + z_2|^2 = (z_1 + z_2)(\overline{z_1 + z_2}) \] ### Step 2: Expand the expression Now, we expand the expression: \[ (z_1 + z_2)(\overline{z_1} + \overline{z_2}) = z_1\overline{z_1} + z_1\overline{z_2} + z_2\overline{z_1} + z_2\overline{z_2} \] ### Step 3: Substitute the modulus Recall that \( |z_1|^2 = z_1\overline{z_1} \) and \( |z_2|^2 = z_2\overline{z_2} \). Thus, we can rewrite the expression as: \[ |z_1 + z_2|^2 = |z_1|^2 + |z_2|^2 + z_1\overline{z_2} + z_2\overline{z_1} \] ### Step 4: Recognize the real part The terms \( z_1\overline{z_2} + z_2\overline{z_1} \) can be rewritten as: \[ 2 \text{Re}(z_1\overline{z_2}) \] So we have: \[ |z_1 + z_2|^2 = |z_1|^2 + |z_2|^2 + 2 \text{Re}(z_1\overline{z_2}) \] ### Step 5: Set the equation According to the problem statement, we have: \[ |z_1 + z_2|^2 = |z_1|^2 + |z_2|^2 \] This implies: \[ |z_1|^2 + |z_2|^2 + 2 \text{Re}(z_1\overline{z_2}) = |z_1|^2 + |z_2|^2 \] ### Step 6: Simplify the equation Subtract \( |z_1|^2 + |z_2|^2 \) from both sides: \[ 2 \text{Re}(z_1\overline{z_2}) = 0 \] ### Step 7: Conclusion This means that: \[ \text{Re}(z_1\overline{z_2}) = 0 \] This indicates that \( z_1 \) and \( z_2 \) are orthogonal in the complex plane, which implies that \( z_1 \) and \( z_2 \) are perpendicular to each other. ### Final Result Thus, the condition for the given equation to hold is: \[ \text{Re}\left(\frac{z_1}{z_2}\right) = 0 \] This means that the real part of the quotient of \( z_1 \) and \( z_2 \) is zero. ---
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