Calculus
posted by saud .
Use the Linear Approximation to estimate ∆f=f(3.5)−f(3) for f(x)=2/(1+x^(2))?
Δf ≈
Estimate the actual change.
(Use decimal notation. Give your answer to five decimal places.)
Δf=
Compute the error and the percentage error in the Linear Approximation.
(Use decimal notation. Give your answer to five decimal places.)
Error =

linear approximation means get the slope.
df/dx=2(2x)/(1+x^2)^2
at at x=3.25, df/dt= 4*3.25/(1+3.25^2)^2=.0972
df=.0972*x but x= 3.53=.5
df=.0488
actual
f(3)=2/(10)=1/5
f(3.5)=2/(1+3.5^2)=.150
f(3.5f(3)=.050
error (.0488.050)/.050 about 2 percent
f(3.5)f(3)=.350 
it says the answer is incorrect