Invalid expression, please help me

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whenever I try to enter this code I keep getting an Invalid expression.

Accepted Answer

Walter Roberson
Walter Roberson on 17 Mar 2021
x = log(abs(3+cos(1.45)^2)) + 6 * exp(-0.2) + log10(5) / sqrt(2) + 5^(-0.8)
maybe. the abs() is questionable. The * after the cos^2 is quite questionable. And I am morally certain that some brackets are missing in the original equation.
Brieuc DANIEL on 17 Mar 2021
I think it may looks like something like that
x = (log(3 + cos(1.45)^2) + 6 * exp(-0.2) + log10(5)) / (sqrt(2+5^-0.8))
Walter Roberson
Walter Roberson on 17 Mar 2021
I see that my moral certainty was correct, that brackets were missing.
For future reference, please note that in mathematics, the operation |x| very frequently means that some kind of magnitude is to be calculated. For example, it is often used to indicate absolute value, but it can also in some contexts mean things like the number of elements in a set, or the length of a string. This is completely different than using [x] which often are just providing brackets for grouping purposes, especially in the tall form like in the diagram; but [] after a word can also indicate a function call, and [] is also used in some contexts to indicate indexing. So... if you see tall [] in an expression and you are transcribing that, transcribe as [] not as solid vertical bars.

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