Find content
Not Telling
Tính $cosx+cos2x+cos3x+...+cosnx$ ($x\neq k2\Pi$)
- nguyenhongsonk612 likes this
hoangkhi813
#556408 Tính $cosx+cos2x+cos3x+...+cosnx$
Posted by
on 26-04-2015 - 13:50
#543418 Giải phương trình $1-x^{2}=6\left \{ x \ri...
Posted by
on 08-02-2015 - 18:01
