\boxed{\text{Artı Değer} = \text{Etki} \times \text{Erişim} - (\text{Zaman} + \text{Dikkat})}

\text{Artı Değer} = \Bigl(\text{Etki} \times \text{Erişim}\Bigr)\Bigl(1+\text{Geçmiş birikim}\Bigr) - \frac{\text{Zaman}+\text{Dikkat}}{1+\text{Geçmiş deneyim}}

\begin{gather} % Use gather environment for centering each line % --- Line 1: A = [Impact x Reach] --- \text{Artı Değer}(t) = \Biggl[ \underbrace{ \biggl( \text{Potansiyel} \times \bigl(\text{Zaman}(t) + \text{Dikkat}(t)\bigr)^{\alpha} \times e^{-\beta\,\bigl(\text{Zaman}(t) + \text{Dikkat}(t)\bigr)} \biggr) }_{\text{Etki} } \times \underbrace{ \Biggl( R_{\text{max}} \frac{\bigl(\text{İlişkiler}(t)\bigr)^{\gamma}}{K_R^{\gamma} + \bigl(\text{İlişkiler}(t)\bigr)^{\gamma}} \Biggr) \times \Biggl( 1 + \lambda_{\text{erişim}} \int_{0}^{t} e^{-k_{\text{erişim}}(t-\tau)} \text{Erişim}(\tau) \,d\tau \Biggr) }_{\text{Erişim}} \Biggr] \notag \\ % Use \notag if you don't want an equation number here % --- Line 2: x [Birikim] --- \times \Biggl( 1 + \underbrace{ \lambda_{\text{birikim}} \int_{0}^{t} e^{-k_{\text{birikim}}(t-\tau)} \max\!\bigl\{0,\;\text{Artı Değer}(\tau)\bigr\} \,d\tau }_{\text{Geçmiş birikim}} \Biggr) \notag % Use \notag if you don't want an equation number here % --- Line 3: - [Cost] --- -\; \frac{ \text{Zaman}(t) + \text{Dikkat}(t) }{ 1 + \underbrace{ \lambda_{\text{deneyim}} \int_{0}^{t} e^{-k_{\text{deneyim}}(t-\tau)} \bigl( \text{Zaman}(\tau) + \text{Dikkat}(\tau) \bigr) \,d\tau}_{\text{Geçmiş deneyim}} } \end{gather}