Question

simplify
${(xy + yz)}^{2} - 2 {x}^{2} {y}^{2}z$
Find the value when x= -1, y=1, z=2​

Answer 1

(xy + yz)² - 2x²y²z

putting values of X = -1 ,y = 1 and z = 2

{(-1)(1) + (2)(1)}² - 2(-1)²(1)²(2)

(-1 + 2)² - 4

1² - 4

1 -4

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