Here's the question you clicked on:
Brooke_army
Evaluate the following definite integral
\[\int\limits_{-1}^{2} \left| X \right| dx\]
I got 3/2 this is the wrong answer the correct answer is 2.5
Can you show me your working ?
\[\left| x \right| \] \[\frac{ x^2 }{ 2 }\] \[(\frac{ 2^2 }{ 2 })- (\frac{ -1^2 }{ 2 })\] (4/2)-(1/2) 3/2
1) Convention suggests that \(X\) is NOT the same as \(x\). Please don't switch variable in the middle of a problem. 2) You have simply ignored the absolute value. That's no good. Split the integral at \(x = 0\) and see if you can manage a different result.
I'm still not sure what to do
|dw:1358608829929:dw|
\(\int\limits_{-1}^{2}|x|\;dx = \int\limits_{-1}^{0}|x|\;dx + \int\limits_{0}^{2}|x|\;dx = \int\limits_{-1}^{0}(-x)\;dx + \int\limits_{0}^{2}(x)\;dx\)
thanks I will try that