<span>sinxcos2x-sin3x=0 ;
</span>sinxcos2x-sin(x+2x) =0 <span>;
</span>sinxcos2x-(sinxcos2x+sin2xcosx) =0 <span>;
</span>sinxcos2x- sinxcos2x - <span>sin2xcosx =0 ;
</span>- sin2xcosx =0 ;
sin2x =0 ⇒2x =π*k⇔ x=π*k/2 ;k<span>∈Z.
</span>cosx =0 ⇒x = π/2 +π*k ;k<span>∈Z.</span>
4*(0,4)-5-0,2x-0,6=-3,8-x
1,6-5-0,2x-0,6=-3,8-x
-0,2x+x= -3,8+0,6+5-1,6
0.8x=0,2
x=0,25
Если так√36 * 5√32, то вот: 6*2= 12.
1. m+m+10=2m+10
2. 70m+90n=10 (7m+9n)
3. (a+a-17)×2=(2a-17)×2=4a-34