Usage of English articles with mathematical equalities
I was curious about how English articles work with cases such as:
For all of the simulations, the B = 15 mT, the f = 10 kHz.
The B and f are of course defined earlier in the text and are used in the same context in the entirety of the text as well. Is it ok to write "the" before each parameter in such sentences? Or should I omit it?
I couldn't find a source that gives a definitive answer on how to use English articles in equations like or equalities like this. I think it's better to omit articles in this case but when I read the sentence in my mind, I read it like "B equals 15 mT" and feel like there should be an article.
B and f are treated as names for the things they represent. Names don't take articles, unless you are The Donald — and even then, Donald is treated rather like a title.
If you were to write "the magnetic flux density was 15mT and the frequency was 10kHz," then you would need an article with the common nouns. Using symbols, you have given the particular instance of that common noun a name.
Consider a similar situation with sentences like "The man had three coins" and "Andrew had three coins": you have given the particular man a name. It doesn't take an article.
You're actually right to read it as "B equals 15mT" or perhaps "B equals fifteen milliteslas".
Just an add-on to A.L.'s answer. When we refer to a variable in an equation or formula, the article is sometimes used and sometimes omitted. This may depend on whether one is referring to the variable as an instance of a symbol or one is referring to its meaning (what the symbol/letter represents) or its (numeric) value. The article is more common when the variable is being referenced as a (written) symbol.
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