Nghiệm của phương trình \(\sin x =  - 1\) là:

\(x = \dfrac{\pi }{2} + k2\pi \).

\(x = \dfrac{k\pi }{2}\).

\(x = k2\pi \).

\(x = \dfrac{\pi }{6} + k2\pi \).

\(y = \sin x\)

\(y = \cos x\)

\(y = \sin 2x\)  

\(y = \cot x\) 

\(\dfrac{{2\pi }}{3}\)

\(\dfrac{\pi }{3}\)

\(\dfrac{{4\pi }}{3}\)

\(\dfrac{{7\pi }}{3}\)

\(\max y = 4;\min y = \dfrac{3}{4}\)

\(\max y = 3;\min y = 2\)

\(\max y = 4;\min y = 2\)

\(\max y = 3,\min y = \dfrac{3}{4}\)

\(\left( {\dfrac{\pi }{2} + k2\pi ;\dfrac{{3\pi }}{2} + k2\pi } \right)\)

\(\left( { - \pi  + k2\pi ;k2\pi } \right)\)

\(\left( {k2\pi ;\pi  + k2\pi } \right)\)                           

\(R\)

\(y = {x^2} - \sin x\)

\(y = {x^2} + \sin x\)

\(y = {x^3} - \sin x\)

\(y = \cos x - {x^2}\)