Respostas

2014-08-08T23:44:54-03:00
A)
 \int\limits^4_2 {x} \, dx = [\frac{x^2}{2} ]\to \frac{4^2}{2} - \frac{2^2}{2} = 8-2=6
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b)
 \int\limits^2_0 {x^2} \, dx =[ \frac{x^3}{3} ]\to \frac{2^3}{3} - \frac{0^3}{3} = \frac{8}{3}
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c)
 \int\limits^9_0 {  \sqrt{x} } \, dx = \int\limits^9_0 {  x^{ \frac{1}{2} } } \, dx =[ \frac{x^{ \frac{1}{2} +1}}{ \frac{1}{2} +1} ]=[ \frac{x^{ \frac{3}{2} }}{ \frac{3}{2} } ]= [\frac{2x^{ \frac{3}{2} }}{3} ]= \frac{2 \sqrt{x^3} }{3} \to \frac{2* \sqrt{9^3} }{3}= \frac{2* \sqrt{729} }{3} \\\\\\= \frac{2*27}{3} =18
2 3 2