1) 121^(-5) * 121 ^ ( - 6) = 121 ^ ( - 5 - 6) = 121 ^ ( - 11 )
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2) 121 ^ ( - 11) / 121 ^ ( -10) = 121 ^ ( - 11 - ( - 10 )) = 121 ^ ( - 11 + 10 ) =
= 121 ^ ( - 1 ) = 1 / 121
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3*(0,9 - 1) - (x+0,6)=-0,2-0,1*(10x+9)=-0,2-х-0,9=-0,2-х=0,7х=-0,7
не знаю, правильно ли или нет)
1 - 0.75= 0.25
0.5 - 0.25 = 0.25
<span>1-cosx=2*sin(x\2) </span>
<span>2sin²(x/2)-2sin(x/2)=0 </span>
<span>sin(x/2)(sin(x/2)-1)=0 </span>
<span>a) sin(x/2)=0 </span>
<span>x/2=πn </span>
<span>x1=2πn </span>
<span>б) </span>
<span>sin(x/2)-1=0 </span>
<span>sin(x/2)=1 </span>
<span>x/2=π/2+2πn </span>
<span>x2=πn+4πn</span>