A.\(\dfrac{{{2^{x + 1}}\ln 2}}{{{{\left( {{2^x} + 1} \right)}^2}}}\)
B.\(\dfrac{{{2^x}\ln 2}}{{{{\left( {{2^x} + 1} \right)}^2}}}\)
C.\(\dfrac{{{2^{x + 1}}}}{{{{\left( {{2^x} + 1} \right)}^2}}}\)
D.\(\dfrac{{{2^x}}}{{{{\left( {{2^x} + 1} \right)}^2}}}\)

A.\(\dfrac{4}{3}\)
B.\(3\)
C.\(2\)
D.\(\dfrac{3}{2}\)

A.\(\dfrac{a}{2}\)
B.\(a\)
C.\(\dfrac{{\sqrt 2 a}}{2}\)
D.\(\sqrt 2 a\)

A.\(\left( P \right):\,\,\,x + y - z = 0\)
B.\(\left( \beta  \right):\,\,\,x + z = 0\)
C.\(\left( Q \right):\,\,\,x + y + 2z = 0\)
D.\(\left( \alpha  \right):\,\,\,x - y + 1 = 0\)

A.\(\dfrac{{{9^x}}}{3} + C\)
B.\(\dfrac{{{9^x}}}{{3\ln 3}} + C\)
C.\(\dfrac{{{9^x}}}{{6\ln 3}} + C\)
D.\(\dfrac{{{9^x}}}{6} + C\)

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

A.\(3\)
B.\(\dfrac{1}{3}\)
C.\(\dfrac{1}{8}\)
D.\(8\)

A.\(\dfrac{{\sqrt 3 {a^3}}}{3}\)
B.\({a^3}\)
C.\(\sqrt 3 {a^3}\)
D.\(\dfrac{{{a^3}}}{3}\)

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

A.\(\left( {2; - 1; - 1} \right)\)
B.\(\left( {1; - 1;0} \right)\)
C.\(\left( {1;1; - 1} \right)\)
D.\(\left( {1; - 2;1} \right)\)