A.\(y = 1\)
B.\(x = 2\)
C.\(x = 1\)
D.\(x =  - 2\)

A.\(\int {f\left( x \right)dx}  =  - \cos x + 2021x + C\)
B.\(\int {f\left( x \right)dx}  = \cos x + 2021x + C\)
C.\(\int {f\left( x \right)dx}  = \cos x + C\) 
D.\(\int {f\left( x \right)dx}  =  - \cos x + C\)

A.\(\frac{{\sqrt 2 }}{3}{a^3}\)
B.\(\frac{{\sqrt 3 }}{3}{a^3}\)
C.\(\frac{{\sqrt 2 }}{4}{a^3}\)
D.\(\frac{{\sqrt 6 }}{3}{a^3}\)

A.\(10\)
B.\(12\)
C.\(6\)
D.\(8\)

A.\(4x - 2y - 2z + 1 = 0\)
B.\( - 2x + y + z + 1 = 0\)
C.\(x + y - 2 = 0\)
D.\( - 2x + y + z + 7 = 0\)

A.\(\left[ \begin{array}{l}m \ge 1\\m \le  - 1\end{array} \right.\)
B.\(m > 0\)
C.\(\left( { - \infty ;0} \right)\)
D.\(\left( {0;1} \right)\)

A.\(4\)
B.\(1\)
C.\(2\)
D.\(3\)

A.\(\sqrt {65} \)
B.\(\sqrt {67} \)
C.\(\sqrt {69} \)
D.\(\sqrt {61} \)

A.\(127\)
B.\(128\)
C.\(63\)
D.\(64\)

A.\(\frac{{7\sqrt 6 }}{4}\)
B.\(\frac{{3\sqrt 3 }}{2}\)
C.\(\frac{{5\sqrt 3 }}{2}\)
D.\(\frac{{7\sqrt 6 }}{2}\)