Cos120= -1/2
sin315= -1/2
cos120+sin315= -1/2+(-1/2)= -1/2 - 1/2= -2/2= -1
(3,5a^15/b^10)*(b^24/0,25a^26)^(1/2) = (3,5*(a^15)*(b^12))/((b^10)*0,5*(a^13) = 7*(a^2)*(b^2)
Уравнение имеет один корень при дискриминанте равном нулю.
Y`=√3/2cos²x -2√3/3
√3/2cos²x -2√3/3=0
√3/2cos²x =2√3/3
cos²x=3/4
(1+cos2x)/2=3/4
2+2cos2x=3
2cos2x=1
cos2x=1/2
2x=+-π/3+2πk
x=+-π/6+πk,k∈z
0≤-π/6+πk≤3π/4
0≤-1+6k≤9/2
1/6≤k≤11/12 нет решения
0≤π/6+πk≤3π/4
0≤1+6k≤9/2
-1/6≤л≤7π/12
k=0 x=π/6
1. 4а - аb^2 + b + b^3 = (4a - ab^2) + (b - b^3) = a (2^2 - b^2) + b(1^2 - b^2) =
= a (2 - b) * (2 + b) + b (1 - b) * (1 + b).
2. bc^2 - 2c^2 - b^3 + 2b^2 = (bc^2 - 2c^2) - (b^3 - 2b^2) = c^2 (b - 2) - b^2 *
* (b - 2)= (b - 2) * (c^2 - b^2) = (b - 2) * (c - b) * (c + b).