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已知x+y+z=0,x^3+y^3+z^3=0,求x^19+y^19+z^19=-----

题目详情
已知x+y+z=0,x^3+y^3+z^3=0,求x^19+y^19+z^19=-----
▼优质解答
答案和解析
x + y = -z x
-z^3 = x^3+y^3 = (x+y)(x^2-xy+y^2) = -z*(x^2-xy+y^2)= -z*[(x+y)^2 - 3xy)] = -z*(z^2-3xy)
z*(-3xy) = 0 xyz = 0; 假设 z = 0;其他的情况同理
x+y = 0 x = -y
x^19 + y^19 + z^19 = (-y)^19 + y^19 + 0^19 = 0