Question

If x = 3 y = 1 z = -4 then find 4x2 + y2 + z2 -4xy- 2yz+ 4zx​

Answer 1

Answer:

=4×2+1×2+(-4)×2-4×(3)×(1)-2×(1)(-4)+4(-4)×(3).

=8+2-8-12-2

=10-22

=-12

Answer 2

Here is your answer