S=30cm², c=60cm, a=2cm ,beta=?
c.v/2=30,c.v=60, v=60/c=60/60=1 ,v=1 cm
sin beta = 1/2, β=30°
Napicyj kartinky, kge cdelaeš vycotu v iz točki na ctopony c treygolnika.
Iz vicoti v i ctoponi BC imeeš 1/2=sinβ.
1)<span>x=4 </span>
<span>3^1-x=1/27 </span>
<span>3^1-x=3^-3 </span>
<span>1-x=-3 </span>
<span>-x=-4 </span>
<span>x=4
2)</span>
-9*(0,7+1,2)/15+0,8=-9*1,9/15+0,8=-1,14+0,8=-0,34