Question

efectuati : (x-2)(x+2)(x^2+4)-(x^2+1)^2+2(x+1)^2

Answer 1

(x-2)(x+2)=$x^{2} -4$

$(x^{2} -4)( x^{2} +4)= x^{4} -16$

$(x^{2} +1)^{2} = x^{4}+2 x^{2} +1$

$2(x+1) ^{2}$=2$x^{2} +2x+1$

Avem:$x^{4} -16- x^{4} -2 x^{2} -1+2 x^{2} +4x+2=4x-15$