А)2*1/2+6*1/2-3√3+9*√3/3=1+3-3√3+3√3=4
б)-√2/2+√2/2-2*1/2-4*1/2=-1-2=-3
в)4*(-1/2)-1*(-1)-3*0=-2+1-0=-1
Sin2a*cos2a*cos4a=(sin4a/2)*cos4a=sin8a/4.
<span>3а (а – b) + (b (2a – b)=3a</span>²-3ab+2ab-b²=3a²-ab+b²<span>
3с (с – 2) – (с – 3)</span>²=3c²-6c-c²+6c-9=2c²-9<span>
(3х + 1) (4х – 2) – 6 (2х – 1)</span>²<span>+ 14=12x</span>² + 4x - 6x - 2 - 24x² + 24x - 6=-12x²+22x-8