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Решите задачу:

$1st. 3^4*9^-^2*27=3^4*(3^2)^-^2*3^3=3^4*3^-^4*3^3=3^3=27$
$2nd. \frac{1+cos(30к)}{2} + \frac{1+cos(150к)}{2} = \frac{1+ \frac{ \sqrt{3} }{2} }{2} + \frac{1- \frac{ \sqrt{3} }{2} }{2} = \frac{2+ \sqrt{3} }{ \frac{2}{2} } + \frac{2- \sqrt{3} }{ \frac{2}{2} } = \\ \frac{2+ \sqrt{3} }{4} + \frac{2- \sqrt{3} }{4} = \frac{2+ \sqrt{3}+2- \sqrt{3} }{4} = \frac{4}{4} = 1$
$3rd. \sqrt[4]{81*0.0001} = \sqrt[4]{0.0081} = \sqrt[4]{ \frac{81}{10000} } = \frac{3}{10} =0.3$