Помоги с 8 и 9 номером

Question

Помоги с 8 и 9 номером

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Answer 1

8. cos(Pi/12)=((1+cos(Pi/6))/2)^(1/2)=((1+cos(30*))/2)^(1/2)=(((2+3^(1/2))^(1/2))/2=0.96592=cos(15*)
9. 2^(1/2)+2*sin(15*)=(2+3^(1/2))^(1/2)