<span>(3*(n+20))=4.5*n </span>
<span>3*n+60=4.5n </span>
<span>1.5n=60 </span>
<span>n=40 - оборотов заднего колеса </span>
<span>x=4.5*n=180 метров</span>
<span>√81=9
</span><span>√25=5
</span>√0,81 - <span>√0,25 = 0,9 - 0,5 = 0,4</span>
4 cos 15°*sin 15°<span> *sin 100</span>°<span>=
= 2*(2</span>cos 15°sin 15°)sin 100°=
= 2 sin 30°sin100°= 2* 1/2 sin100° = sin100°=
= sin(90°+10°) = cos10°
1/sin170-√3/sin100=1/sin(180-10)-√3/sin(90+10)=
=1/sin10-√3/cos10=(cos10-√3sin10)/(sin10cos10)=
2*(1/2*cos10-√3/2*sin10)/(1/2*sin20)=4sin(30-10)/sin20=4sin20/sin20=4