giải pt
1. $2cos^{2}(\frac{\pi }{4}+3x)=1+sin4x+2sin5xcos^{2}x$
2.
$2sin(x+\frac{\pi }{3})+2cos(\frac{x}{2}+\frac{\pi
}{4})=3sin(\frac{x}{4}+\frac{\pi }{8})+\sqrt{3}cos(\frac{x}{4}+\frac{\pi
}{8})$
3. $sin^{2}(2+3x)+cos^{2}(\frac{\pi }{4}+2)=cos^{2}(2-5x)+sin^{2}(\frac{\pi }{4}-6x)$