What is the area of a triangle with side lengths 6, 8, and 10 using Heron's formula?
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Find the value(s) of x in the interval [0, 2π] for which f(x) = cot x is equal to zero.
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Write a math question for the theme "Characteristics of cosine function f(x) = cos x":What is the amplitude, period, and domain of the function f(x) = cos(x)? How many x-intercepts does it have?