Question

Consideram numarul N=(3x²+y²)-(x²+1)+(1-y²). Calculati N , daca x=2 si y=-4

Answer 1

N=(3x²+y²)-(x²+1)+(1-y²) . 
x = 2 , y = -4 . 

N = [(2*2²+(-4²)]-(2²+1)+[(1-(-4)²] 

N = (8 + 16 ) - 5 + (1-16) 

N = 24-5-15

N = 4