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Find the modulus of the following using ...

Find the modulus of the following using the property of modulus
`(3+4i) (8-6i)`

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To find the modulus of the complex number expression \((3 + 4i)(8 - 6i)\), we can use the property of modulus of complex numbers. Here’s the step-by-step solution: ### Step 1: Identify the Complex Numbers Let: - \( z_1 = 3 + 4i \) - \( z_2 = 8 - 6i \) ### Step 2: Find the Modulus of \( z_1 \) The modulus of a complex number \( z = x + iy \) is given by: \[ |z| = \sqrt{x^2 + y^2} \] For \( z_1 = 3 + 4i \): - \( x = 3 \) - \( y = 4 \) Calculating the modulus: \[ |z_1| = \sqrt{3^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5 \] ### Step 3: Find the Modulus of \( z_2 \) Now, for \( z_2 = 8 - 6i \): - \( x = 8 \) - \( y = -6 \) Calculating the modulus: \[ |z_2| = \sqrt{8^2 + (-6)^2} = \sqrt{64 + 36} = \sqrt{100} = 10 \] ### Step 4: Use the Property of Modulus The property of modulus states that: \[ |z_1 z_2| = |z_1| \cdot |z_2| \] Thus, we can find the modulus of the product: \[ |z_1 z_2| = |z_1| \cdot |z_2| = 5 \cdot 10 = 50 \] ### Final Answer The modulus of the expression \((3 + 4i)(8 - 6i)\) is: \[ \boxed{50} \] ---
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ICSE-COMPLEX NUMBERS-Exercise (C)
  1. Find the modulus of (1-i)^(-2) + (1+ i)^(-2)

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  2. If z= 6+8i, verify that |z|= |bar(z)|

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  3. If z= 6+8i, verify that -|z| le " Re " (z) le |z|

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  4. If z= 6+8i, verify that -|z| lt "Im" (z) lt |z|

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  5. If z= 6+8i, verify that z^(-1)= (bar(z))/(|z|^(2))

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  6. If z(1)=3 + 4i,z(2)= 8-15i, verify that |-z(1)| = |z(1)|

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  7. If z(1)=3 + 4i,z(2)= 8-15i, verify that |z(1)^(2)| = |z(2)|^(2)

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  8. If z(1)=3 + 4i,z(2)= 8-15i, verify that |z(1)z(2) |= |z(1)| |z(2)|

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  9. If z(1)=3 + 4i,z(2)= 8-15i, verify that |(z(1))/(z(2))|= (|z(1)|)/(...

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  10. If z(1)=3 + 4i,z(2)= 8-15i, verify that |z(1) + z(2)| lt |z(1)| + ...

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  11. If z(1)=3 + 4i,z(2)= 8-15i, verify that |z(2)-z(1)| gt ||z(2)|- |z...

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  12. If z(1)=3 + 4i,z(2)= 8-15i, verify that |z(1) + z(2)|^(2) + |z(1)-...

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  13. Find the modulus of the following using the property of modulus (3+...

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  14. Find the modulus of the following using the property of modulus (8+...

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  15. Find the modulus of the following using the property of modulus (3+...

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  16. Find the modulus of the following using the property of modulus ((2...

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  17. Let z be a complex number such that |(z-5i)/(z+5i)|=1, then show that ...

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  18. Find the complex number z satisfying the equation |(z-12)/(z-8i)|= (5)...

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  19. If z is a complex number such that |z-1|= |z+1|, show that Re(z)= 0

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  20. Solve |z|+z= 2+ i, where z is a complex number

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