cau 2

Câu hỏi: cau 2

A a,x=\frac{5\pi }{18}+\frac{k2\pi }{3}

b,3

B a,   x=\frac{5\pi }{18}+\frac{k2\pi }{3}  hoặc  x=\frac{7\pi }{6}+k2\pi

b,z=10+3i

C a, x=\frac{7\pi }{6}+k2\pi

b, 3

D a,     x=\frac{5\pi }{18}+\frac{k2\pi }{3} hoặc x=\frac{7\pi }{6}+k2\pi

b,3