一个数学题我看不懂:(

sh_kevin · 发表于 2008-8-26 23:09:00

A certain circle in the xy-plane has its center at the origin. If P is a point on the circle, what is the sum of the squares of the coordinates of P?

(1) The radius of the circle is 4.

(2) The sum of the coordinates of P is 0.

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

大牛帮个忙吧答案是a

sophiess · 发表于 2008-8-26 23:23:00

觉得lx说的对,我怕误导LZ,把解释删了

我很久没接触过G了,现在还要重拾起来

一起加油吧!

[此贴子已经被作者于2008-8-27 8:36:49编辑过]

stonebeard · 发表于 2008-8-27 05:13:00

不对吧,题意要求的是坐标的平方的和,就是x^2+y^2,不是正方形

p点仅仅在圆上.

根据圆方程,x^2+y^2=r^2,所以1足够了.

条件2仅仅说明点p在方程x+y=0上,没有圆半径条件,所以不行

sh_kevin · 发表于 2008-8-27 10:27:00

the sum of the squares of the coordinates of P 要求的是坐标的平方的和

知道了本来还不理解是什么意思

所属分类: GMAT考试