Barbara Szwal
Grupa I1E1S1
VP = w12s12 + w22s22 + 2w1w2s1s2ρ12
Po podstawieniu w2 = 1 − w1 obliczeniu pochodnej po w1 i przyrównaniu do zera otrzymujemy:
$$V_{P} = \frac{s_{1}^{2}s_{2}^{2}(1 - \rho_{12}^{2})}{s_{1}^{2} + s_{2}^{2} - 2s_{1}s_{2}\rho_{12}}$$
$$w_{1} = \frac{s_{2}^{2} - s_{1}s_{2}\rho_{12}}{s_{1}^{2} + s_{2}^{2} - 2s_{1}s_{2}\rho_{12}}$$
$$w_{2} = \frac{s_{1}^{2} - s_{1}s_{2}\rho_{12}}{s_{1}^{2} + s_{2}^{2} - 2s_{1}s_{2}\rho_{12}}$$