Question

if x = 2 and y=1 then prove that (x-y)²=x²-2xy+y²​

Answer 1

Answer:

Step-by-step explanation:

L.H.S= (x-y)২

=(2-1)২

=1

R.h.s=x২-2xy+y২

=4-4 +1

=1

Haha..It was so easy

Answer 2

Answer\Step-by-step explanation:

0≤(x − y)^2 ⟹ 0≤x^2−2xy+y^2

                  ⟹ 2xy≤x^2+y^2

             ⟹ xy≤ x2+y2\2

                  ⟹ xy≤ x^2+y^2

since the clearly nonnegative real x^2+y^2

clearly satisfies x^2+y^2\2  ≤x^2+y^2.