Equivalent Capacitance of a set of Capacitors

[NotCarlSagan]

Homework Statement

Homework Equations

1/C_eq= 1/C₁ + 1/C₂

The Attempt at a Solution

1/C_13eq= 1/3C₁ + 1/5C₃ = 8C/3 = 2.67C

1/C_12eq= (3C x C)/(3C + C) = 0.75C

C_eqtotal = 2.67C + 0.75C = 3.42C

I think the series circuit is throwing me off?

 

[voko]

Consider the combination of C2 and C3 as a single capacitor in series with C1.

 

[CWatters]

Homework Equations

1/C_eq= 1/C₁ + 1/C₂

That's the equation for caps in series. What about the equation for caps in parallel?