I have learned a lot of formulas for converting trigonometric values, but when I looked up sin(pi/10) I got the exact answer (1/4)(√5 +1). I tried to arive at this using formulas, but I couldn't. How is this found? What other angles can be found exactly.(adsbygoogle = window.adsbygoogle || []).push({});

Ps. I already know about how taylor series and how they can be used.

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# For what angles can the exact value of all trigonometrig ratios be found?

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