Update docs/src/catalyst_applications/bifurcation_diagrams.md

Co-authored-by: Sam Isaacson <[email protected]>

Author: TorkelE

docs/src/catalyst_applications/bifurcation_diagrams.md

@@ -109,7 +109,7 @@ plot(bif_dia; xguide="d", yguide="Xp")
 This bifurcation diagram does not contain any interesting features (such as bifurcation points), and only shows how the steady state concentration of $Xp$ is reduced as $d$ increases. 
 
 Finally, for additional clarity, we reiterate the purpose of the two `u` arguments used:
-- `u_guess`: A guess of the initial steady states (which BifurcationKit uses to find its starting point). Typically, most trivial guesses work (e.g. setting all species concentrations to `1.0`). `u_guess` *does not* have to fulfil the conserved concentrations provided in `u0`.
+- `u_guess`: A guess of the initial steady states (which BifurcationKit uses to find its starting point). Typically, most trivial guesses work (e.g. setting all species concentrations to `1.0`). `u_guess` *does not* have to fulfill the conserved concentrations provided in `u0`.
 - `u0`: Used to compute the concentrations of any conserved quantities (e.g. in our example $X + Xp = 1.0$). Technically, values are only required for species that are involved in conservation laws (in our case we do not need to provide a value for $K$). However, sometimes determining which species are actually involved in conservation laws can be difficult, and it might be easier to simply provide concentrations for all species.
 
 !!! note