Question

DAU COROANĂ!!!
Este urgent!​

Answer 1

Răspuns:

E(x,y) = 3⁴ = 81

Explicație pas cu pas:

E(x,y) = (x²+2xy)(x²+2xy+2y²)+y⁴

x+y = 3  => E(x,y) = 81 ?

-------------------------

E(x,y) =x⁴+2x³y+2x²y²+2x³y+4x²y²+4xy³+y⁴ = >

E(x,y) = x⁴+4x³y+6x²y²+4xy³+y⁴ = (x+y)⁴ =>

E(x,y) = 3⁴ = 81

(x+y)⁴ = (x+y)²(x+y)² = (x²+2xy+y²)(x²+2xy+y²) =

= x⁴+2x³y+x²y²+2x³y+4x²y²+2xy³+x²y²+2xy³+y⁴ =

= x⁴+4x³y+6x²y²+4xy³+y⁴