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Can someone show me the meaning of this symbol? I've googled but couldn't find it
1 Answer
$\begingroup$It is called nabla, which is the name of the symbol but not it's meaning.
In Calculus, you can find it (alone) as an operator meaning "denotes the vector of partial derivatives":
$$\nabla = \left(\frac{\partial}{\partial x},\ \frac{\partial}{\partial y},\ \frac{\partial}{\partial z}\right)$$
If you are in three dimensions.
In your case, the $x$ subscripts indicates the only $x$ component of the gradient:
$$\nabla_x = \frac{\partial}{\partial x}$$
More herewhat does ∇ (upside down triangle) symbol mean in this problem∇-upside-down-triangle-symbol-mean-in-this-problem?noredirect=1&lq=1
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