- Messages
- 2,884
- Reaction score
- 415
- Points
- 93
absolute errors in sum or diffrence
u=x+y or u=x-y
the error in u will be
error in x+error iny
absolute error in product or quotient
u=xy or u=x/y
error of u/ u= +or- ( error of x/x + error of y/y)
absolute error for index form
eg u=x^2 y
error of u/u= +or- ( 2times error of x/x + error of y/y)
error for lg or ln
suppose
I=1.2+or-o.1
Imax=1.3
Imin=1.1
lg of Imax=0.114
lg of Imin=0.0414
error in lg I= ( lgmax - lg min)/2
=(0.114-0.0414)/2
=0.0363
=0.04
error should always be to 1d.p, so the data should also be to 1 d.p
ie error should always be to 1s.f
u=x+y or u=x-y
the error in u will be
error in x+error iny
absolute error in product or quotient
u=xy or u=x/y
error of u/ u= +or- ( error of x/x + error of y/y)
absolute error for index form
eg u=x^2 y
error of u/u= +or- ( 2times error of x/x + error of y/y)
error for lg or ln
suppose
I=1.2+or-o.1
Imax=1.3
Imin=1.1
lg of Imax=0.114
lg of Imin=0.0414
error in lg I= ( lgmax - lg min)/2
=(0.114-0.0414)/2
=0.0363
=0.04
error should always be to 1d.p, so the data should also be to 1 d.p
ie error should always be to 1s.f