-2x^3+2x^2-6x+2x^6+x^2-5x=-2x^3+3x^2+2x^6-11x=-57+27+1458-33=1395
lim_{x->2} (2x-x^2)/(4-x^2) = lim_{x->2} x(2-x)/((2+x)(2-x)) = lim_{x->2} x/(2+x) = 2/(2+2) = 1/2,
lim_{x->4} (√x-2)/(8-2x) = lim_{x->4} (√x-2)/(-2(x-4)) = lim_{x->4} (√x-2)/(-2(√x+2)(√x-2)) = lim_{x->4} -1/(2(√x+2)) = -1/(2(√4+2) = -1/8;
lim_{x->0} (√1-x-1)/x^2 = lim_{x->0} -x/x^2 = lim_{x->0} -1/x = -∞,
lim_{x->0} 5sin(x/2)/(2x) = lim_{x->0} 5sin(x/2)/(4*x/2) = 5/4 lim_{x->0} sin(x/2)/(x/2) =5/4 *1 = 5/4.
180(градусов) - 65=115(градусов) (ABC)
ABC равен углу 123
ответ угол123=115
(m+n)*(m-n)-(3m^2-n^2)=m²-mn+mn-n²-3m²+n²=-2m²