The given function `f(x) = arctan(sqrt(x))` is in a inverse trigonometric form.
The basic derivative formula for inverse tangent is:
`d/(dx) arctan(u) = ((du)/(dx))/sqrt(1-u^2)` .
Using u-substitution, let `u = sqrt(x)` then
`u^ 2 = (sqrt(x))^2 = x`
For the derivative of u or `(du)/(dx)` , we apply the Power Rule:
`d/dx(x^n)=n*x^(n-1) * d(x)`
This is possible since `sqrt(x) = x^(1/2)`
Then ` d/(dx) x^(1/2) = 1/2 * x^(1/2-1)* 1` Note: `d/(dx) (x) = 1`
`=1/2 x^(-1/2) `
Applying the Law of Exponents: `x^(-n)=1/x^n` .
`(du)/(dx) =1/2 * x^(-1/2) `
`= 1/2 * 1/ x^(1/2)`
` =1/(2 x^(1/2) ) or1/(2 sqrt(x))`
We now have: `u=sqrt(x)` and `(du)/(dx) =1/(2sqrt(x))` .
Applying the formula` d/(dx) arctan(u)= ((du)/(dx))/(1+u^2)` :
`f'(x) = d/(dx)arctan(sqrt(x))=(1/(2sqrt(x)))/(1+(sqrt(x))^2)`
`f'(x) =(1/(2sqrt(x)))/(1+x)`
`f'(x) =1/(2sqrt(x))* 1/(1+x) `
`f'(x) =1/(2sqrt(x)(1+x))`
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