Question

prove it by trigonometry concept

Answer 1

I hope it helps u....

Answer 2

Hello! 

1. you did not provide a proper question 
2. I cannot understand your hand-writing so I hope I this is right!

Okay! I have gotten $4+ \sqrt{2} \sqrt{5+ \sqrt{5}$ /8 - 1  
(DECIMAL; 0.02447)

Please let me know if you need any help! I'd love to help you with any other assessments 

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