Сумма и разность кубов
m^3 + n^3 = (m + n)(m^2 - mn + n^2)
125 + n^3 = (5 + n)(25 - 5n + n^2)
1/(125m^3) - 27 = (1/(5m) - 3)(1/(25m^2) + 3/(5m) + 9)
27n^3 - 64m^3 = (3n - 4m)(9n^2 + 12nm + 16m^2)
Ав = (1;0;0)
|ab|=1
ас = (0;1;0)
|ac|=1
(ав*ас) = |ab| * |ac| * cos(alpha) = 0+0+0=0
cos(alpha)=0
sin(alpha)=1
S=1/2 * |ab| * |ac| * sin(alpha) = 0,5 - это ответ
Sin(A - B)=sinAcosB-<span>cosAsinB
</span><span>sin5xcos6x - cos5xsin6x = sin (5x - 6x) = sin ( - x) = - sinx
f ' (x) = ( - sinx) ' = - cosx </span>
Х^3 / х+у=-2^3/-2+1/3=-8/-2=1/3=4:1/3=4/1:1/3=4/1*3/1=12/1=12