[hahajamiexlyn]

how do you find the domain of

y=sqrt(tanx)
and
y=x/cosx


I can't figure these out for the life of me! Yikesss

[ebaines]

The domain is the set of values that the independent variable can take on for the function be valid. Here that means finding the set of values of x that would be allowable. Here's a hint for the first one - you can't take the square root of a negative number, so therefore tan(x) must be greater than or equal to zero. Now, what set of values of x lead to tan(x) meeting that condition? Can you take it from here?

[s_cianci]

A square root function must have a non-negative domain. Furthermore, there are certain points for which tan is undefined. Combine the two and you've got your first question answered. For your second question, denominators must be non-zero. Any value that would cause your denominator to be 0 must be excluded from the domain. As these are trigonometric functions and are therefore periodic is there a specified interval stated for these problems?