For a function of two variables z=f(x,y), the gradient is the two-dimensional vector <f_x(x,y),f_y(x,y)>. This definition generalizes in a natural way to functions of more than three variables. For the function z=f(x,y)=4x^2+y^2.
By this definition, about 10% of people who smoke marijuana become addicted to it. (More on Time.com: PHOTOS â Cannabis Conventions). However, nonspecialists (including many doctors) still tend to use an older perspective, now seen as outdated by experts.
Marijuana, just like any other drug, can lead to addiction. It affects the brainâs reward system in the same way as all other drugs of addiction â and the likelihood of addiction increases considerably for those who start young.any users roll loose marijuana into a cigarette called a âjoint.â Marijuana can also be smoked in a pipe or water pipe (called a âbongâ) or vaporized using a âvapeâ pen. A single intake of smoke from a joint or pipe is called a hit. Marijuana can also be mixed into food or brewed as tea and ingested.