Trigonometri

Question

$Sin80 - \frac{sin10}{\sqrt{3}}+ \frac{sin50}{\sqrt{3}}$

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Cevap kök3.cos40

Answer 1

$sin(80)+\frac{1}{\sqrt{3}}.(sin(50)-sin(10))$

$sin(50)-sin(10)=2.cos(\frac{50+10}{2}).sin(\frac{50-10}{2})=\frac{\sqrt{3}}{2}.sin20$  gelir.

Buradan $sin(80)+sin(20)=2.(sin(\frac{80+20}{2})+cos(\frac{80-20}{2}))=\sqrt{3}.cos40$