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 However, nonspecialists (including many doctors) still tend to use an older perspective, now seen as outdated by experts.
Risks of Marijuana Use. Though you may have heard otherwise, marijuana can be addictive: Nearly 10% of people who use it become dependent on it. It isnât clear whether marijuana is a gateway drug that makes people more likely to try harder drugs like cocaine and heroin.The amount of THC in marijuana has gone up in recent years.isks of Marijuana Use. Though you may have heard otherwise, marijuana can be addictive: Nearly 10% of people who use it become dependent on it. It isnât clear whether marijuana is a gateway drug that makes people more likely to try harder drugs like cocaine and heroin.