$$\pi$$  

$$\frac{\pi}{2}$$  

$$\frac{\pi}{18}$$  

$$2\pi$$  

$$\frac{180}{\pi}rad$$  

$$\frac{\pi}{180}rad$$  

$$\pi\ rad$$  

$$180rad$$  

$$\cot\alpha=\tan\beta$$  

$$\cos\alpha=\sin\beta$$  

$$\cos\beta=\sin\alpha$$  

$$\cot\beta=-\tan\alpha$$  

1

-1

$$\frac{-4}{5}$$

$$\frac{-6}{5}$$

$$\tan x=\frac{\sin x}{\cos x}$$  

$$\cot x=\frac{\cos x}{\sin x}$$  

$$\tan x.\cot x=1$$  

$$\sin x=1-\cos x$$  

A

B

C

D

$$\sin^2x+\cos^2x=1$$

$$\tan x=\frac{\sin x}{\cos\ x}$$

$$\tan x\cos x=1$$

$$1+\tan^2x=\frac{1}{\cos^2x}$$

$$\sin4a=2\sin4a\cos4a^{ }$$

$$\sin6a=2\sin6a\cos6a$$

$$\cos2a=\sin^2a-\cos^2a$$

$$\cos4a=1-2\sin^22a$$

$$\cos a+\cos b=\cos\frac{a+b}{2}\cos\frac{a-b}{2}$$

$$\cos a-\cos b=2\sin\frac{a+b}{2}\sin\frac{a-b}{2}$$

$$\sin a+\sin b=2\sin\frac{a+b}{2}\cos\frac{a-b}{2}$$

$$\sin a-\sin b=-2\cos\frac{a+b}{2}\sin\frac{a-b}{2}$$

$$\cos a+\cos b=2\cos\frac{a+b}{2}\cos\frac{a-b}{2}$$

$$\cos a\cos b=\frac{1}{2}\left(\cos\left(a+b\right)-\cos\left(a-b\right)\right)$$

$$\sin a\sin b=\frac{1}{2}\left(\cos\left(a-b\right)-\cos\left(a+b\right)\right)$$

$$\sin a\cos b=\frac{1}{2}\left(\sin\left(a+b\right)+\sin\left(a-b\right)\right)$$

$$2\sin\frac{3x}{2}.\cos\frac{7x}{2}$$  

$$-2\sin\frac{7x}{2}.\sin\frac{3x}{2}$$  

$$2\sin\frac{7x}{2}.\sin\frac{3x}{2}$$  

$$2\cos10x.\cos4x$$  

$$2\cos10x.\sin4x$$  

$$2\cos5x.\cos2x$$  

$$-2\cos2x.\sin5x$$  

$$2\sin4x.\cos2x$$  

$$2\sin2x.\cos4x$$  

$$2\cos4x.\sin2x$$  

$$2\sin4x.\sin2x$$  

$$-2\cos\frac{5x}{2}.\sin\frac{9x}{2}$$  

$$2\sin\frac{9x}{2}.\cos\frac{5x}{2}$$  

$$2\cos\frac{9x}{2}.\sin\frac{5x}{2}$$  

$$\frac{1}{2}\left(\cos5x-\cos9x\right)$$  

$$\frac{1}{2}\left(\cos5x+\cos9x\right)$$  

$$\frac{1}{2}\left(\sin5x+\sin9x\right)$$  

$$\frac{1}{2}\left(\sin\left(-2x\right)+\sin8x\right)$$  

$$\frac{1}{2}\left(\cos8x+\cos\left(-2x\right)\right)$$  

$$\frac{1}{2}\left(\cos\left(-2x\right)-\cos8x\right)$$  

$$\frac{1}{2}\left(\sin x+\sin5x\right)$$  

$$\frac{1}{2}\left(\cos x+\cos5x\right)$$  

$$\frac{1}{2}\left(\cos x-\cos5x\right)$$  

$$\sin\left(-x\right)$$  

$$\sin x$$  

$$\sin\pi$$  

$$-\sin x$$  

$$\tan2x$$  

$$-\tan2x$$  

$$\tan\left(-2x\right)$$  

$$-\tan x$$  

$$\sin\left(-x\right)$$  

$$\sin x$$  

$$-\sin x$$  

$$\cos\left(-x\right)$$  

$$\sin\frac{x}{3}$$  

$$\cos\frac{x}{3}$$  

$$-\cos\frac{x}{3}$$  

$$\sin\left(-\frac{x}{3}\right)$$  

$$\sin x>0$$  

$$\cos x>0$$  

$$\tan x>0$$  

$$\cot x>0$$  

A

B

C

D

A

B

C

D

$$\cos u+\cos v=\frac{1}{2}\left(\cos\left(\frac{u+v}{2}\right)\cos\left(\frac{u-v}{2}\right)\right)$$

$$\cos u+\cos v=-2\sin\left(\frac{u+v}{2}\right)\sin\left(\frac{u-v}{2}\right)$$

$$\sin u+\sin v=2\sin\left(\frac{u+v}{2}\right)\cos\left(\frac{u-v}{2}\right)$$

$$\sin u+\sin v=2\sin\left(\frac{u-v}{2}\right)\cos\left(\frac{u+v}{2}\right)$$

$$\cos2a=\sin^2a-\cos^2a$$

$$\cos2a=1-2\cos^2a$$

$$\cos2a=2\sin^2a-1$$

$$\sin^2\alpha+\cos^2\alpha=1$$

$$\sin\alpha+\cos\alpha=1$$

$$\tan\alpha+\cot\alpha=1$$

$$\tan^2\alpha=1+\cos^2\alpha$$

$$\cos\alpha=-\frac{\sqrt{5}}{5}$$  

$$\cos\alpha=\frac{\sqrt{5}}{5}$$  

$$\cos\alpha=\frac{1}{5}$$  

$$\cos\alpha=-\frac{1}{5}$$  

$$\sin a\cos a.$$  

$$4\sin a\cos a.$$  

$$2\sin a\cos a.$$  

$$\frac{\sin a\cos a}{2}.$$  

$$\sin2a=\frac{−24}{25}​;\cos2a=\frac{7}{25}$$  

$$\sin2a=\frac{24}{25}​;\cos2a=\frac{7}{25}$$  

$$\sin2a=\frac{24}{25}​;\cos2a=\frac{-7}{25}$$  

$$\sin2a=\frac{−24}{25}​;\cos2a=\frac{-7}{25}$$  

$$\sin(−α)=−\sinα.$$  

$$\tan\left(-\alpha\right)=\tan\alpha.$$  

$$\cot\left(-\alpha\right)=-\cot\alpha.$$  

$$\cos(−α)=\cosα.$$  

$$\sin(π−α)=\sinα.$$  

$$\cos(π−α)=\cosα.$$  

$$\tan(π−α)=−\tanα.$$  

$$\cot(π−α)=−\cotα.$$  

$$\sin\left(\alpha+\beta\right)$$  

$$\sin\left(\alpha-\beta\right)$$  

$$\cos\left(\alpha+\beta\right)$$  

$$\cos\left(\alpha-\beta\right)$$  

$$\sin^2x$$  

$$-\sin^2x$$  

$$\sin x$$  

$$-\sin x$$  

$$-\cot\alpha$$

$$\cot\alpha$$

$$-\tan\alpha$$

$$\tan\alpha$$

$$2\sqrt[]{2}$$

$$-2\sqrt[]{2}$$

$$3\sqrt[]{2}$$

$$-3\sqrt[]{2}$$

1

2

4

4sinx.cosx

$$\cot\alpha<0$$

$$\sin\alpha>0$$

$$\cos\alpha<0$$

$$\tan\alpha<0$$

$$135\degree$$  

$$72\degree$$  

$$270\degree$$  

$$240\degree$$  

x

- 2x

$$\frac{\pi}{2}-x$$

$$\frac{\pi}{2}-2x$$

$$-x$$  

$$\pi-x$$  

$$\frac{\pi}{2}-x$$  

$$\pi+x$$  

- x

$$\frac{\pi}{2}-x$$  

$$\pi-x$$  

$$\pi+x$$  

$$-\sin\ x$$  

$$\sin\ x$$  

$$\cos\ x$$  

$$-\cos x$$  

$$\cos\ 2x$$  

$$\cos\ \alpha$$  

$$\sin\ \alpha$$  

$$\sin2\alpha$$  

$$-\sin x+\cos x+\tan x$$  

$$\sin x-\cos x+\cot x$$  

$$-\sin x+\cos x+\cot x$$  

$$-\sin x-\cos x+\cot x$$  

$$\frac{\pi}{6}$$  

$$\frac{\pi}{3}$$  

$$\frac{\pi}{4}$$  

$$\frac{\pi}{2}$$  

$$30^o$$  

$$45^o$$  

$$60^o$$  

$$150^o$$  

$$\frac{7}{2}\pi$$  

$$\frac{7}{4}\pi$$  

$$\frac{2}{7}\pi$$  

$$\frac{4}{7}\pi$$  

$$\cos a.\cos b-\sin a.\sin b$$  

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

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

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

$$858\degree$$

$$558\degree$$

$$855\degree$$

$$120\degree$$

$$1020\degree$$  

$$-1020\degree$$  

$$1080\degree$$  

$$-1140\degree$$  

32,46cm

32,47cm

32,5cm

32,45cm

$$\frac{13\pi}{4}$$

$$585\degree$$

$$\frac{15\pi}{4}$$

$$\frac{-13\pi}{4}$$

$$\sin\ 12a$$  

$$2\sin7a$$  

$$2\sin6a$$  

$$2\sin12a$$  

$$M=\cos8a=\cos^2a-\sin^2a$$  

$$M=\cos8a=\cos^22a-\sin^22a$$  

$$M=\cos8a=\cos^24a-\sin^24a$$  

$$M=\cos8a=\cos^26a-\sin^26a$$  

$$\cos5a-\cos3a=2\cos4a.\cos a$$  

$$\cos5a-\cos3a=2\sin4a.\sin a$$  

$$\cos5a-\cos3a=-2\sin a.\sin4a$$  

$$\cos5a-\cos3a=2\sin4a.\cos a$$  

$$\cos2a.\cos3a=\frac{1}{2}\left[\cos5a+\cos a\right]$$

$$\cos2a.\sin3a=\frac{1}{2}\left[\sin5a-\sin a\right]$$

$$\sin2a.\sin3a=\frac{1}{2}\left[\cos5a-\cos a\right]$$

cùng chiều

ngược chiều

trục hoành Ox / hoành độ

trục tung Oy / tung độ

$$\cos5x$$

$$\cos x$$

$$\sin5x$$

$$\sin x$$

$$\frac{\sin x}{\cos x}$$  

$$\frac{\sin a}{\cos a}$$  

$$\frac{\sin2x}{\cos2x}$$  

$$\frac{\sin2a}{\cos2a}$$