Question: Show that the following equivalences hold. c. E_1 (E_2 - e_3) = (E_1 E_2 - E_1 E_3) d. sigma_theta_1^theta_2 (E_1 E_2) = sigma_theta_1 (E_1 (sigma_theta_2(E_2))),

Show that the following equivalences hold. c. E_1 (E_2 - e_3)

Show that the following equivalences hold. c. E_1 (E_2 - e_3) = (E_1 E_2 - E_1 E_3) d. sigma_theta_1^theta_2 (E_1 E_2) = sigma_theta_1 (E_1 (sigma_theta_2(E_2))), where theta_2 involves only attributes from E_2. Show that the following equivalences hold. c. E_1 (E_2 - e_3) = (E_1 E_2 - E_1 E_3) d. sigma_theta_1^theta_2 (E_1 E_2) = sigma_theta_1 (E_1 (sigma_theta_2(E_2))), where theta_2 involves only attributes from E_2

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