Tìm cực trị của hàm số:
z(x, y)=1/3x^3+xy^2+2xy

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Asap will give brainiest to first person to answer what is the measure of angle b in the triangle? enter your answer in the box.m∠b=

Identify all the cases where non-probability sampling is used when attempting to study the characteristics of a large city. studies on every subject in the population divide a population in groups and obtain a sample studies with a limited amount of time demonstrate existing traits in a population studies with the nth person selected