If  then the value of  is

• 0

• 1

• 2

• 3

If a³ - b³ = 56  and a - b = 2, then what is the value of a² + b² ?

• 12

• 20

• 28

• 32

If x² - 3x + 1 = 0,   then the value of  is

• 1

• 0

• 3

• 2

If  then the value of  is:

• 2

• 1

• 0

• 

If    and xyz = -1, then x³ + y³ + z³ is equal to:

• -1

• 1

• -2

• 2

The value of  is

• 

• -1

• 2ab

• 1

167.

If  then the value of 

• 1

• -1

• 4

• 

If  then the value of x² + 2x - 1 is

• 

• 4

• 0

• 3

If  then the value of  is:

• 23

• 16

• 34

• 32

If a(x + y) =  b(x - y)  = 2ab, the the value of 2(x² + y²) is

• 2 (a² - b²)

• 2(a² + b²)

• 4(a² - b²)

• 4(a² + b²)