I really appreciate, if somebody could help me with these tasks, I am beginner and really need fast help. Also, as my mothertonque is not English, some mathematical terms may be wrong, hope you understand.
1. Function y=ln (x+10/x-8)+80
a)find domain, b)asymptotes equations, c)Extremums, d)grow and decline areas, e)curvature and concava areas, f)point of inflections
2.Function: z=xy+40x, a) find Extremums in condition: x^2+y^2=256
b) control sufficiency, c) designate type, d) calculate the value of function