Question

solve i. xy2-(xy-yz)-z

Answer 1

Step-by-step explanation:

Answer

(xy+yz)

2

−2x

2

y

2

z when x=−1,y=1,z=2

⇒[y(x+z)]

2

−2x

2

y

2

z

⇒y

2

[x

2

+z

2

+2xz−2x

2

z]

⇒(1)

2

[(−1)

2

+2

2

+2(−1)(2)−2(−1)

2

(2)]

⇒[1+4−4−4]⇒−3

∴(xy+yz)

2

−2x

2

y

2

z at x=−1,y=1 and z=2 is −3