A.\(P = \sqrt {ab} \)
B.\(P = \dfrac{1}{{\sqrt[4]{{ab}}}}\)
C.\(P = \sqrt[4]{{ab}}\)
D.\(P =  - \sqrt[4]{{ab}}\)

A.\(\dfrac{{x - 1}}{1} = \dfrac{{y - 2}}{3} = \dfrac{{z + 2}}{1}\)   
B.\(\dfrac{x}{{ - 1}} = \dfrac{{y - 1}}{{ - 1}} = \dfrac{{z - 3}}{5}\)
C.\(\dfrac{{x + 1}}{1} = \dfrac{{y + 2}}{3} = \dfrac{{z - 2}}{1}\)   
D.\(\dfrac{{x + 1}}{1} = \dfrac{{y + 1}}{2} = \dfrac{{z - 5}}{{ - 2}}\)

A.\(672\)  
B.\(483\)   
C.\(3.\left( {{2^{21}} - 1} \right)\)   
D.\({3^{21}} - 1\)

A.\(P = \dfrac{{\sqrt {10} }}{2}\)  
B.\(P = 2\sqrt {10} \)   
C.\(P = \sqrt {10} \)   
D.\(P = 2\)

A.\(2 - \sqrt 2 \)  
B.\(1\)    
C.\(2 + \sqrt 2 \)   
D.\(2\)

A.\(I = \int\limits_1^3 {{t^2}dt} \)  
B.\(I = \int\limits_1^3 {tdt} \)   
C.\(I = \int\limits_1^{{e^4}} {{t^2}dt} \)   
D.\(I = 2\int\limits_1^3 {{t^2}dt} \)

A.\({45^o}\)
B.\({90^o}\)
C.\({30^o}\)
D.\({60^o}\)

A.\(\left( {4;8} \right)\)  
B.\(\left( {4;9} \right)\)   
C.\(\left( {0;4} \right) \cup \left( {8; + \infty } \right)\)  
D.\(\left[ {4;8} \right]\)

A.\(\left( P \right):x + 2y - 3z + 9 = 0\)   
B.\(\left( P \right):x + 2y - 3z - 9 = 0\)
C.\(\left( P \right):x + 2y + 3z - 9 = 0\)   
D.\(\left( P \right):x + \sqrt 3 y - 1 - \sqrt 3  = 0\)

A.-1   
B.1    
C.-2    
D.2