( (1/x)^arctg(3x) )' = ( (x)^(-arctg3x) )' = -arctg(3x)*x^(-arctg3x - 1) * 3/(1 + 9x^2) = -3*arctg(3x) / ((1+9x^2)*(x^arctg3x + 1))
arcsin 1 - arccos(-1/2)=(П/2)-(2*П/3)=(3*П-2*2*П)/6=(3*П-4*П)/6=-*П/6
A^2+4a+4-4a+7^2= 8a^2+4
подставляем:
8*(1\2)^2+4= 8*1\4+4= 2+4=6
(3a² - a + 2)(2a - 3) = 6a³ <u>- 9a²</u> <u>- 2a²</u> + <em>3a</em> +<em> 4a</em> - 6 = 6a³ - 11a² + 7a - 6