Find z when sec(z) = 3i

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Homework Statement



Find the value of z when sec(z) = 3i.

Homework Equations



sec (z) = 1/cos(z)

The Attempt at a Solution



I assume that I need to transform into polar coordinates and then use some transformations. I'm really at a loss. If not a solution maybe a few hints to go in the right direction?

Thanks in advance.
 
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Questioneer said:

Homework Statement



Find the value of z when sec(z) = 3i.

Homework Equations



sec (z) = 1/cos(z)
Good start. And, since you are working with complex numbers, cos(z)= (eiz+ e-iz)/2. So you have
[tex]\frac{2}{e^z+ e^{-z}}= i[/itex]<br /> which can be reduced to <br /> [itex]e^{iz}+ e^{-iz}= -2i[/itex]<br /> and that can be converted to a quadratic.<br /> <br /> <blockquote data-attributes="" data-quote="" data-source="" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> <h2>The Attempt at a Solution</h2><br /> <br /> I assume that I need to transform into polar coordinates and then use some transformations. I'm really at a loss. If not a solution maybe a few hints to go in the right direction? </div> </div> </blockquote> Don't assume things!<br /> <br /> <blockquote data-attributes="" data-quote="" data-source="" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> Thanks in advance. </div> </div> </blockquote>[/tex]