Answer:
as written, no
perhaps yes as intended
Explanation:
The function written here is ...
f(x) = (e^-11)x
f(x) ≈ 0.0000167017x . . . . a linear function
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Perhaps you intend ...
f(x) = e^(-11x)
This has the variable in the exponent, so is an exponential function.
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The Order of Operations requires exponents be evaluated before multiplication. That is why the multiplication of -11 by x is not performed the way the function is written. Rather, the exponent e^-11 is evaluated, then the result is multiplied by x.
If that is not what you intend, then parentheses are required in order to force the operations you want in the order you want.