# Equivalent resistance in simple Current Circuit

I have the following circuit (below). In order to calculate the current I1 as a function of the resistors and the voltage of the circuit, I'm doing the following:

$$R_{eq} = (R1 //R2 +R3); R_{eq}I = V \iff I = \frac{V}{R_{eq}} = \frac{V}{R3 + \frac{R1+R3}{R1R2}}$$

I know that

$$V = 1 V, R1 = R2 = R3 = 2 \Omega$$

So the current should be

$$I = \frac{1}{2 + 1} = .333$$

However, the textbook gives the expression for I (Agarwal and Lang(2005) Foundations of Analog and Digital, page 152):

$$R_{eq} = (R1 //R2 +R3); R_{eq}I = V \iff I = = \frac{1V}{2\Omega + 2\Omega}$$

I don't get what I did wrong. Those resistors R2 and R1 are in parallel so wouldn't it be the equivalent resistance R1//R2 + R3?

simulate this circuit – Schematic created using CircuitLab