5^-9*(5^2)^-2/(5^3)^-4=5^(-9-4+12)=5^-1=1/5=0,2
㏒₃17=m
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㏒₃51 =㏒₃ 3*17=㏒₃ 3+㏒₃17=1+m
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㏒₂₇17 =㏒₃³ 17= 1/3㏒₃17 =1/3*m
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㏒₂₇51 = ㏒₃³ 3*17=㏒₃³ 3+㏒₃³ 17 =1/3*1 +1/3㏒₃ 17 =1/3 + 1/3*m=1/3*(1+m)
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2㏒₉ 153 =2㏒₃² 153= 2* 1/2 ㏒₃ 153 =㏒₃ 9*17=㏒₃9 +㏒₃17 =㏒₃3² +㏒₃ 17=
=2*㏒₃3+㏒₃17= 2*1+m =2+m
Угол А=180-(70+60)=50
дуга ВС=100,⇒угол ВОС=100
F ' (x0) = k = tga
k - ?
f ' (x) = (sinx + cosx) ' = cosx - sinx
f ' (pi/2) = cos pi/2 - sin pi/2 = 0 - 1 = - 1
О,Ваше задание решено!Ответ во вложении!!!