т.к.ctg=cos/sin,то <span>1+cos(-a)/sin(-a)-ctg(-a)</span>=<span>1+(cos(-a)/sin(-a))-cos(-a)/sin(-a)=1</span>
<span>Arcsin1+arccos0-2arctg0</span>π/2 + π/2 - 2*0 = π<span><span>
</span></span>
D2= 2s/d1*sina
<span>d2= 42/42/11
</span><span>d2=11</span>