Update README.md

README.md

@@ -381,7 +381,7 @@ Compute the Reynolds number *Re* and the Darcy friction factor *f* given the sam
 `hQthk2fDRe` computes both the Darcy friction factor *f* and the Reynolds number *Re* given the head loss *h*, the pipe's length *L* and roughness *k*, the volumetric flow rate *Q*, the gravitational acceleration *g*, and the fluid's density *ρ* and dynamic viscosity *μ*. Replacing hydraulic diameter *D* in the Darcy-Weisbach equation by the Reynolds number *Re*,
 
 $$
-{Re^5 f}={2ghQ^3 \over\displaystyle {{\left[ {\pi \over 4} \right]}^3 {\left[ {\mu \over \rho} \right]}^5 L}}
+{Re^5 f}={2ghQ^3 \over\displaystyle {\left[ {\pi \over 4} \right]^3 {\left[ {\mu \over \rho} \right]}^5 L}}
 $$
 
 Along with the Colebrook-White equation, this version of the Darcy-Weisbach equation produces a system of two equations with two variables. Solution is computed iteratively.