sin a cos (pi/3) - cosa sin (pi/3) - sin a cos (pi/3)- cosa sin(pi/3) = -2cosa sin(pi/3) = -2*(корень из 3)/2 cosa = -(корень из 3)cos a
(8x^4+11y^2)^2=64(x^4)^2+2*8x^4*11y^2+121(y^2)^2=64x^8+176x^4y^2+121y^4
1. t²-tu-2t+2u=t(t-u)-2(t-u)=(t-u)(t-2)
2. ab-ac-bt+ct+c-b=a(b-c)-t(b-c)-(b-c)=(b-c)(a-t-1)
1) (2a+b)^2 2) (0,2x-y)^2
3) (5a-3x)^3 4)
5) (3ab-x) (3ab+x) 6) (-x-2y) (-x+2y)
7) (0,2p+q) (q-0,2) 8) (3-a) (9+3a+a^2)
<span>9) (2x+3y) (4x^2-6xy+9y^2)fda</span>