Given `f(x)=(2x)/(1+x^2)^2, [0, 2]`
Average Value Formula=`1/(b-a)int_a^bf(x)dx`
`f_(ave)=1/(2-0)int_0^2(2x)/(1+x^2)^2dx`
`=(1/2)*2int_0^2x/(1+x^2)^2dx`
`=int_0^2x/(1+x^2)^2dx`
Integrate using the u-subsitution method.
Let `u=1+x^2`
`(du)/dx=2x`
`dx=(du)/(2x)`
`=int_0^2x/u^2*(du)/(2x)`
`=(1/2)int_0^2(1/u^2)du`
`=(1/2)int_0^2(u^-2)du`
`=(1/2)(u^-1)/(-1)|_0^2`
`=(-1/2)[1/u]_0^2`
`=(-1/2)[1/(1+x^2)]_0^2`
`=(-1/2)[1/(1+(2)^2)-1/(1-0^2)]`
`=(-1/2)[1/5-1]`
`=(-1/2)(-4/5)`
`=2/5`
The average value is 2/5.
Given `f(x)=(2x)/(1+x^2)^2, [0, 2]`
Average Value Formula=`1/(b-a)int_a^bf(x)dx`
`f_(ave)=1/(2-0)int_0^2(2x)/(1+x^2)^2dx`
`=(1/2)*2int_0^2x/(1+x^2)^2dx`
`=int_0^2x/(1+x^2)^2dx`
Integrate using the u-subsitution method.
Let `u=1+x^2`
`(du)/dx=2x`
`dx=(du)/(2x)`
`=int_0^2x/u^2*(du)/(2x)`
`=(1/2)int_0^2(1/u^2)du`
`=(1/2)int_0^2(u^-2)du`
`=(1/2)(u^-1)/(-1)|_0^2`
`=(-1/2)[1/u]_0^2`
`=(-1/2)[1/(1+x^2)]_0^2`
`=(-1/2)[1/(1+(2)^2)-1/(1-0^2)]`
`=(-1/2)[1/5-1]`
`=(-1/2)(-4/5)`
`=2/5`
The average value is 2/5.
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