\uparrow height

[pozitron57]

\uparrow, \downarrow has the height of the line (version 0.11).

$v=\sqrt{\dfrac{GM}{r\downarrow}} \Rightarrow v \uparrow$

XeLaTeX:

Ziamath:

[pozitron57]

Probably the same issue:

$\langle u \rangle = \sqrt{\dfrac{\langle u_1 \rangle^2+\langle u_2 \rangle^2}{2}}$