天山 3-16

vineyard

if S^4*V^3*X^7<0,is SVX<0?

(1) V<0

(2) X>0

I got C while the key is E,

can anyone explain it for me?

考G进行时

因为  x^4 是正的,并不能说明X的正负

vineyard

以下是引用考G进行时在2005-3-3 7:26:00的发言：
因为  x^4 是正的,并不能说明X的正负

where is the X^4 from?

考G进行时

S^4

vineyard

以下是引用考G进行时在2005-3-3 7:33:00的发言：
S^4

thank you.

suddenly realized what the question is