Question

104 помогите!!!!!!!!!!!!!!!!!!!

Answer 1

$1)quad tg2 alpha =1; ,; ; alpha in [-pi ,pi ]\\2 alpha =frac{pi}{4}+pi n,; nin Z\\ alpha =frac{pi}{8}+frac{pi n}{2}; ,; nin Z\\ alpha in [-pi ,pi ]; :; ; alpha =-frac{7pi}{8}; ,; -frac{3pi}{8}; ,; frac{pi }{8}; ,; frac{5pi }{8}\\2)quad cos2 alpha =0; ,; ; alpha in [-2pi ,2pi ]\\2 alpha =frac{pi}{2}+pi n,; nin Z\\ alpha =frac{pi}{4}+frac{pi n}{2},; nin Z\\ alpha in [-2pi ,2pi ]:\\alpha =- frac{7pi }{4},-frac{5pi }{4},; -frac{3pi }{4},; -frac{pi }{4},; frac{pi }{4},; frac{3pi }{4},; frac{5pi }{4},; frac{7pi }{4}; .$

$3)quad sin2 alpha =0; ,; alpha in [0,2pi ]\\2 alpha =pi n,; nin Z\\ alpha =frac{pi n}{2},; nin Z\\ alpha in [0,2pi ]:; ; alpha =0,; frac{pi}{2},; pi ,; frac{3pi }{2},; 2pi ; .$

$4)quad cos2 alpha =-1; ,; ; alpha in [-3pi ,0]\\2 alpha =pi +2pi n,; nin Z\\ alpha =frac{pi}{2}+pi n,; nin Z\\ alpha in [-3pi ,0]:; ; alpha =-frac{5pi}{2},; -frac{3pi}{2},; -frac{pi}{2}; .$