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if z=3 -2i, then verify that (i) z...

if z=3 -2i, then verify that
(i) ` z + barz = 2Rez`
(ii) ` z - barz = 2ilm z `

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To verify the given statements for the complex number \( z = 3 - 2i \), we will follow these steps: ### Step 1: Find the conjugate of \( z \) The complex conjugate of a complex number \( z = x + iy \) is given by \( \bar{z} = x - iy \). For our case: \[ z = 3 - 2i \implies \bar{z} = 3 + 2i \] ### Step 2: Calculate \( z + \bar{z} \) Now, we will calculate \( z + \bar{z} \): \[ z + \bar{z} = (3 - 2i) + (3 + 2i) \] Combine the real and imaginary parts: \[ z + \bar{z} = 3 + 3 + (-2i + 2i) = 6 + 0i = 6 \] ### Step 3: Calculate \( 2 \text{Re}(z) \) The real part of \( z \) is: \[ \text{Re}(z) = 3 \] Now, calculate \( 2 \text{Re}(z) \): \[ 2 \text{Re}(z) = 2 \times 3 = 6 \] ### Step 4: Verify \( z + \bar{z} = 2 \text{Re}(z) \) From our calculations: \[ z + \bar{z} = 6 \quad \text{and} \quad 2 \text{Re}(z) = 6 \] Thus, we have: \[ z + \bar{z} = 2 \text{Re}(z) \quad \text{(Verified)} \] ### Step 5: Calculate \( z - \bar{z} \) Now, we will calculate \( z - \bar{z} \): \[ z - \bar{z} = (3 - 2i) - (3 + 2i) \] Combine the real and imaginary parts: \[ z - \bar{z} = 3 - 3 + (-2i - 2i) = 0 - 4i = -4i \] ### Step 6: Calculate \( 2i \text{Im}(z) \) The imaginary part of \( z \) is: \[ \text{Im}(z) = -2 \] Now, calculate \( 2i \text{Im}(z) \): \[ 2i \text{Im}(z) = 2i \times (-2) = -4i \] ### Step 7: Verify \( z - \bar{z} = 2i \text{Im}(z) \) From our calculations: \[ z - \bar{z} = -4i \quad \text{and} \quad 2i \text{Im}(z) = -4i \] Thus, we have: \[ z - \bar{z} = 2i \text{Im}(z) \quad \text{(Verified)} \] ### Conclusion Both statements have been verified: 1. \( z + \bar{z} = 2 \text{Re}(z) \) 2. \( z - \bar{z} = 2i \text{Im}(z) \)
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AAKASH INSTITUTE ENGLISH-COMPLEX NUMBERS AND QUADRATIC EQUATIONS-Try Yourself
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  10. Represent the modulus of 3+4i in the Argand plane.

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  11. Represent the modulus of 1+i, in the Argand plane.

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  12. Find the modulus of (2 -3i)/( 4+i)

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  13. Find the modulus of ((3+2i)^(2))/(4-3i)

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  14. If z(1)=5+2i and z(2)=2 +i ,verify (i) |z(1)z(2)|= |z(1)||z(2)|

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  17. Find the modulus and argument of -3.

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  18. Convert the complex number (1+i)/(1-i) in the polar form

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  19. Convert the complex number 4/(1-isqrt3) in the polar form.

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