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If 8i z^3+12 z^2-18 z+27 i=0,t h e n |z...

If `8i z^3+12 z^2-18 z+27 i=0,t h e n` `|z|=3/2` b. `|z|=2/3` c.`|z|=1` d. `|z|=3/4`

A

`|z| = (3)/(2)`

B

`|z| = (3)/(4)`

C

`|z|=1`

D

`|z| = (3)/(4)`

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To solve the equation \(8i z^3 + 12 z^2 - 18 z + 27 i = 0\) and find the modulus of \(z\), we can follow these steps: ### Step 1: Rearranging the equation The given equation is: \[ 8i z^3 + 12 z^2 - 18 z + 27 i = 0 \] ### Step 2: Factoring out common terms We can factor the equation by grouping terms. Notice that we can take \(4i\) as a common factor from the first and last terms: \[ 4i(2z^3 + \frac{12}{4i} z^2 - \frac{18}{4i} z + \frac{27}{4i}) = 0 \] This simplifies to: \[ 4i z^2(2z - \frac{3}{2}i) + 9 = 0 \] ### Step 3: Setting up the factors We can separate the equation into two parts: 1. \(2z - 3i = 0\) 2. \(4iz^2 - 9 = 0\) ### Step 4: Solving the first equation From the first equation: \[ 2z - 3i = 0 \implies 2z = 3i \implies z = \frac{3i}{2} \] Now, we find the modulus of \(z\): \[ |z| = \left|\frac{3i}{2}\right| = \frac{3}{2} \] ### Step 5: Solving the second equation From the second equation: \[ 4iz^2 - 9 = 0 \implies 4iz^2 = 9 \implies z^2 = \frac{9}{4i} \] To find \(z\), we can multiply the numerator and denominator by the conjugate of the denominator: \[ z^2 = \frac{9}{4i} \cdot \frac{-i}{-i} = \frac{-9i}{-4} = \frac{9i}{4} \] Now, taking the modulus: \[ |z|^2 = \left| \frac{9i}{4} \right| = \frac{9}{16} \] Thus, \[ |z| = \sqrt{\frac{9}{16}} = \frac{3}{4} \] ### Conclusion The possible values of \(|z|\) from the equations are \(\frac{3}{2}\) and \(\frac{3}{4}\). The correct answer from the options provided is: - **Option a: \(|z| = \frac{3}{2}\)**

To solve the equation \(8i z^3 + 12 z^2 - 18 z + 27 i = 0\) and find the modulus of \(z\), we can follow these steps: ### Step 1: Rearranging the equation The given equation is: \[ 8i z^3 + 12 z^2 - 18 z + 27 i = 0 \] ...
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