Please explain this answer ☹️
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Answer:
see explanation
Step-by-step explanation:
Note that cos315° = cos45° and sin315° = - sin45° and
cos45° = sin45° = [tex]\frac{1}{\sqrt{2} }[/tex] = [tex]\frac{\sqrt{2} }{2}[/tex]
Hence
12(cos315° + isin315°)
= 12(cos45° - isin45°)
= 12([tex]\frac{\sqrt{2} }{2}[/tex] - i [tex]\frac{\sqrt{2} }{2}[/tex])
= 6[tex]\sqrt{2}[/tex] - 6i [tex]\sqrt{2}[/tex]