Tinh A+B, A-B,B-A
a)A = 6 – 6y + y4 – 3x2 + x3
B = y3 – y4 + \(\dfrac{1}{2}\)x2 – 3x2 + \(\dfrac{2}{3}\)
b) A= 5 – \(\dfrac{1}{3}\)x + 4x3- x2
B = x – 2x3+ 4x3-1+2x4
2) Tim da thuc P,Q
a) P + x2 – y2 = x2+y2+z2
b) ( x2 + 2xy + y2) – Q = x2-y2-2xy
mn giup e voi a ! Cau nao cung dc , ngay mai la e phai nop roi mong mn giup do ! E cam on truoc a !