How do I evaluate the integral of (sin(2t)^2)^(1/2) ?
I had to evaluate an integral from 0 to 2pi in which the integrand was sqrt(sin(2x)^2). I figured the square root of sin(2x) squared was just sin(2x). Evaluating the integral gave me 0, which makes sense since the function is symmetric. But this was "incorrect".
Apparently sqrt(sin(2x)^2) = |sin(2x)|. How would I express the integral of the absolute value of a function? (Please generalize your answer so that it explains cases for which the function is not symmetric.)
|sin(2x)| = sin(2x) and -sin(2x) so would the integral of |sin(2x)| from 0 to 2pi be the sum of the integral of sin(2x) and the integral of -sin(2x) from 0 to 2pi?
Re: How do I evaluate the integral of (sin(2t)^2)^(1/2) ?
It should be obvious that the sum of sin(2x) and -sin(2x) is 0 and so the sum of the integrals will be 0!
The basic definition of "absolute value" is that |x|= x if , -x is x< 0.
So |sin(2x)|= sin(2x) if and -sin(2x) if which is the same as
|sin(2x)|= sin(2x) if [tex]0\le x\le \pi/2[/itex] and -sin(2x) if
If you want to integrate from 0 to , you will also need to use the fact that, sine is periodic with period , sin(x) is positive for and negative for so |sin(2x)|= sin(2x) for and |sin(2x)|= -sin(2x) for