<span>sin/ (1-cost)=(1+cost)/sin t;
</span><span>sin t/ (1-cos t)-(1+cos t)/sin t= (sin</span>²t-(1-cos²t))/((1-cos t)sin t)=(sin²t-1+cos²t)/((1-cos t)sin t)=(1-1)/((1-cos t)sin t)=0.<span>
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(x + 6)(x + 14) = x^2 + 14x + 6x + 84 = x^2 + 20x + 84
s=4*t, где s-путь пройденный пешеходом, t-время в пути.
(3х-2у)÷(у+2.2), при х=0.7; у=-0.2
(3*0.7-2*(-0.2))
2.1+0.4÷2
2.5÷×
1.25