Je was op zoek naar: finding equation of tangent line at a point (Spaans - Engels)

*"notice respecting the deposition of metallic copper from is solutions by slow voltaic action at a point equidistant from the metallic surfaces", "report of the eighth meeting of the british society for the advancement of science", vol.
*"notice respecting the deposition of metallic copper from is solutions by slow voltaic action at a point equidistant from the metallic surfaces", "report of the eighth meeting of the british society for the advancement of science", vol.

since the differential at a point (for a differentiable function):formula_18is a linear map it has a well defined inverse if, and only if, "dfx" is a bijection.
; second remarksince the differential at a point (for a differentiable function): formula_4is a linear map, it has a well-defined inverse if and only if "dfx" is a bijection.

====spherical form====the potential "v"(r) at a point r outside the charge distribution, i.e., _r_ > "r"max, can be expanded by the laplace expansion,:formula_21where formula_22 is an irregular solid harmonic (defined below as a spherical harmonic function divided by "r""l+1") and formula_23 is a regular solid harmonic (a spherical harmonic times r"l").
===spherical form===the potential "v"(r) at a point r outside the charge distribution, i.e., _r_ > "r"max, can be expanded by the laplace expansion::formula_30where formula_31 is an irregular solid harmonic (defined below as a spherical harmonic function divided by formula_32) and formula_33 is a regular solid harmonic (a spherical harmonic times r"ℓ").