Is x4 + y4 > z4 ?
(1) x2 + y2 > z2
(2) x + y > z
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
误将题目看作条件去判断。。。不等式两边同时平方可以进行判断。
A选项平方的结果是:x^4+y^4+2x^2y^2>z^4,但不能推出x^4+y^4>z^4
登录 或 注册 后可以参加讨论