Giải phương trình:
$1) 8sin^{2}x+3sin2x+3sinx+cos x=1$
$2)\frac{2sin^{5}x}{sinx+cosx}+\frac{1}{2}sin2x=sin^{4}x+cos^{4}x+sin^{2}xcos^{2}x$
$3) \left ( sinx+cosx \right )^{4}=4+cos^{4}4x$
$4) \sqrt{sinx}+\sqrt{cosx}=1$
$5) sin3x-cos3x+\frac{1}{sinx+cosx}=2sin2x$
$6) \frac{1}{cosx cos2x}+\frac{1}{cos2x cos3x}+\frac{1}{cos3x cos4x}=0$
$7) tan\left ( \frac{\Pi }{3}+3x \right )=\sqrt{3}+tanx+tan2x$