If x + y + z = 4, xy + yz + zx = 1 and x3+ y3 + z3 = 34, then what is the value of 2xyz?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. -12
Given that
If x + y + z = 4, xy + yz + zx = 1 and x3+ y3 + z3 = 34
As we know
x3+ y3 + z3 - 3xyz = (x + y + z) ((x + y + z)2 - 3 * (xy + yz + zx))
Put the value in this equation
34 - 3xyz = 4 * ( 16 - 3* 1)
3xyz = -52 + 34 = -18
xyz = -6
2xyz = -12