Product Rule. If the two functions f(x) and g(x) are differentiable (i.e. the derivative exist) then the product is differentiable and, The proof of the Product Rule is shown in the Proof of Various Derivative Formulas section of the Extras chapter.
Inflammation is the most common reason for muscle pain and aches. Any time that major inflammation exists (strep throat, hepatitis, cancer, lupus, acute heart attack, etc.), signs and symptoms often include fevers, sweats, chills, fatigue, weight loss, and various muscle aches, pains and weakness.
Approximately two-thirds of people with lupus will develop some type of skin disease, called cutaneous lupus erythematosus. Skin disease in lupus can cause rashes or sores (lesions), most of which will appear on sun-exposed areas such as the face, ears, neck, arms, and legs.40-70 percent of people with lupus will find that their disease is made worse by exposure to ultraviolet (UV) rays from sunlight or artificial light.ubacute cutaneous lesions may appear as areas of red scaly skin with distinct edges or as red, ring-shaped lesions. The lesions occur most commonly on the sun-exposed areas of the arms, shoulders, neck, and body. The lesions usually do not itch or scar, but they can become discolored.