ÔN TẬP LƯỢNG GIÁC

sina.sinb + cosa.cosb

sina.cosb + cosa.sinb

sina.cosb - cosa.sinb

sina.sinb - cosa.cosb

cosa.sinb - sina.cosb

cosa.sinb - sina.cosb

cosa.cosb + sina.sinb

cosa.sinb + sina.cosb

$$30^o$$  

$$45^o$$  

$$60^o$$  

$$150^o$$  

$$x=k2\pi;k\in Z$$

$$x=\pi+k2\pi;k\in Z$$

$$x=k\pi;k\in Z$$

$$x=\frac{\pi}{2}+k\pi;k\in Z$$

$$x\ne\pi+k2\pi;\ k\in Z$$

$$x\ne k\pi\ ;k\in Z$$

$$x\ne\frac{\pi}{2}+k\pi\ ;k\in Z$$

$$x\ne\frac{\pi}{2}+k2\pi\ ;k\in Z$$

$$x=\pm\frac{\pi}{6}+k2\pi;\ k\in Z$$

$$x=\pm\frac{\pi}{4}+k2\pi;\ k\in Z$$

$$x=\pm\frac{\pi}{3}+k2\pi;\ k\in Z$$

$$x=\pm\frac{\pi}{2}+k2\pi\ ;\ k\in Z$$

$$x\ne\pi+k2\pi;\ k\in Z$$

$$x\ne k\pi\ ;\ k\in Z$$

$$x\ne\frac{\pi}{2}+k\pi;\ k\in Z$$

$$x\ne\frac{\pi}{2}+k2\pi;\ k\in Z$$

$$\cos a.\cos b-\sin a.\sin b$$  

$$\cos a.\cos b+\sin a.\sin b$$

$$\sin a.\cos b-\cos a.\sin b$$

$$\sin a.\cos b+\cos a.\sin b$$

$$\frac{7}{2}\pi$$  

$$\frac{7}{4}\pi$$  

$$\frac{2}{7}\pi$$  

$$\frac{4}{7}\pi$$