A symmetric split is accepted only from equal capacitor sources. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

A split row first proves the two capacitances match

The midpoint is accepted only from two equal-capacitance sources across the same rail.

Ca=Cb=2 FVs=8 VC_a=C_b=2\ \text{F}\quad V_s=8\ \text{V}
Equal-capacitor splitThe midpoint comes from checked equal capacitances.Vs 8 VVfly 4 VVout 4 Vmode split

Equal split keeps the midpoint at one half of the rail

Each row rebuilds the split from two equal capacitors and a different source rail.

VsVmidsources8 V4 Vequal10 V5 Vequal12 V6 Vequal\begin{array}{c|c|c}V_s&V_{\text{mid}}&\text{sources}\\8\ \text{V}&4\ \text{V}&\text{equal}\\10\ \text{V}&5\ \text{V}&\text{equal}\\12\ \text{V}&6\ \text{V}&\text{equal}\\\end{array}

Equal source capacitors split the rail

The split row cites two equal capacitance sources before accepting the midpoint.

8 V/2=4 V8\ \text{V}/2=4\ \text{V}
Equal-capacitor splitThe midpoint comes from checked equal capacitances.Vs 8 VVfly 4 VVout 4 Vmode split