Question

Trebuie de adus la o forma Mai simpla :
a)(x+y)(x-y)-(x^2+3y^2)
b)2a(a+1)-(a-2)(a+4)

Answer 1

a)$x^{2} - y^{2} -( x^{2} + 3y^{2} )= x^{2} - y^{2} - x^{2} - 3y^{2}=-4 y^{2}$
b)$2a(a+1)-(a-2)(a+4)=2a ^{2} +2a-(a ^{2} +4a-2a-8)=$$2a ^{2} +2a-(a ^{2} +2a-8)=2a ^{2} +2a-a ^{2} -2a+8= a^{2} +8$