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o0oone in a milliono0o

o0oone in a milliono0o

Đăng ký: 03-06-2012
Offline Đăng nhập: 24-02-2013 - 16:56
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$\frac{\sqrt{3}}{2cos^{2}x}+...

14-01-2013 - 16:11

giải pt: $\frac{\sqrt{3}}{2cos^{2}x}+\frac{2+sin2x}{sin2x}=\frac{1}{tanx}+1+\sqrt{3}$

$48-\frac{1}{cos^{4}x}-\frac{2}...

14-01-2013 - 16:10

giải pt: $48-\frac{1}{cos^{4}x}-\frac{2}{sin^{2}x}(1+cotx.cot2x)=0$

$\frac{sin2x+cos2x+5sinx-cosx-3}{2cosx-\sqrt{3}...

14-01-2013 - 12:16

giải pt:
1)$\frac{sin2x+cos2x+5sinx-cosx-3}{2cosx-\sqrt{3}}=0$
2)$48-\frac{1}{cos^{4}x}-\frac{2}{sin^{2}x}(1+cotx.cot2x)=0$
3)$\frac{\sqrt{3}}{2cos^{2}x}+\frac{2+sin2x}{sin2x}=\frac{1}{tanx}+1+\sqrt{3}$

$2\left ( sinx-cosx \right )+sin3x+cos3x=3\sqrt{2}(2+sin2...

13-01-2013 - 12:03

giải pt: $2\left ( sinx-cosx \right )+sin3x+cos3x=3\sqrt{2}(2+sin2x)$

$abc= 1$. CMR: $\frac{a^{2}}{(ab+2)(2ab+1...

05-12-2012 - 22:23

Cho số thực $a,b,c$ thoả $abc= 1$. CMR:
$\frac{a^{2}}{(ab+2)(2ab+1)}+\frac{b^{2}}{(bc+2)(2bc+1)}+\frac{c^{2}}{(ac+2)(2ac+1)}> \frac{1}{3}$