• indet1: script to determine an approximation of F(x) knowing an approximation of x. At the beginning F(x) = x·sin(x³) is calculated.
function F(x) { with(Math) { y = x*sin(pow(x,3) return y }}
If x = 2 ± 0.05, what is the value of F(x)? With "click1" I have a quick evaluation. With "click2" I have a better evaluation.
F(x) = 1.74 ± 0.26.
• indet2:
script to determine an approximation of F(x,y) knowing approximations of x and y.
At the beginning
function F(x,y) { with(Math) { u = log(x+y)*sqrt(xy) return u }}
If x = 5 ± 0.5, y = 3 ± 0.5, what is the value of F(x,y)?
F(x,y) = 2.84 ± 0.76.
• indet3:
script to determine an approximation of F(x,y,z) knowing approximations of x, y and z.
At the beginning function F(x,y,z) { with(Math) { u = x*y*sin(z*PI/180) return u }} If x = 9.80 ± 0.02, y = 0.3 ± 0.006, z = 30 ± 1, what is the value of F(x,y,z)? 
F(x,y,z) = 1.471 ± 0.077, or 1.47 ± 0.08 (? is about half of 0.3 kg, as we would have expected, taking into account the width of the angle).
• indet4:
script to determine an approximation of F(x,y,z,w) knowing approximations of x, y, z, w.
At the beginning

function F(x,y,z,w) { with(Math) { u = (xy)/(z+w) return u }}
F(x,y,z,w) = (2.4845 ± 0.0009)·10^{−8}
• indet5 and indet6: scripts to determine an approximation of the length and an approximation of the direction of the sum of two vectors knowing approximations of these ones
An example of use, if a vector is of length 20±0.5 and direction (30±0.5)° and the second vector is of length 12±0.5 and direction (50±0.5)°.
indet5:
indet6:
The sum has length 31.55 ± 1.02, or 31.5 ± 1.1, and direction (37.47 ± 0.80)°, or (37.5 ± 0.9)°.
What is F in indet5:
function F(x,y,z,w) { with(Math) {
u = sqrt( pow(cos(x*PI/180)*z+cos(y*PI/180)*w,2) + pow(sin(x*PI/180)*z+sin(y*PI/180)*w,2) )
return u
}}
What is F in indet6:
function F(x,y,z,w) { with(Math) {
u = atan( (sin(x*PI/180)*z+sin(y*PI/180)*w) / (cos(x*PI/180)*z+cos(y*PI/180)*w) )*180/PI
return u
}}