Two long straight parallel wires are a distance d part. They carry...

The magnetic field in between because of each will be in opposite direction. $B_{\text{in between }}=\frac{\mu_{0} i}{2 \pi x} \hat{\mathbf{j}}-\frac{\mu_{0} i}{2 \pi(2 d-x)}-\hat{\mathbf{j}} =\frac{\mu_{0} i}{2 \pi}\left[\frac{1}{x}-\frac{1}{2 d-x}\right] \hat{\mathbf{j}}$ At $x=d, B_{\text{in between }}=0$ For $x < d, B_{\text{in between }}=\hat{\mathbf{j}}$ For $x>d, B_{\text{in between }}=-\hat{\mathbf{j}}$ Towards $x$, net magnetic field will add up and direction will be $(-\hat{\mathbf{j}})$. Towards $x^{\prime}$, net magnetic field will add up and direction will be $(\hat{\mathbf{j}})$.