Unit circle review

 $\sin x$  is positive in

• the 1st and 2nd quadrants

• the 1st and 3rd quadrants

• the 2nd and 3rd quadrants

• the 3rd and 4th quadrants

• the 1st and 2nd quadrants

• the 1st and 3rd quadrants

• the 2nd and 3rd quadrants

• the 1st and 4th quadrants

 $\tan x$  is negative in

• the 1st and 2nd quadrants

• the 1st and 3rd quadrants

• the 2nd and 4th quadrants

• the 1st and 4th quadrants

Exact value of  $\sin45\degree$  

•  $\frac{1}{2}$  

•  $\frac{\sqrt{2}}{2}$  

•  $\frac{\sqrt{3}}{2}$  

•  $\sqrt{3}$  

Exact value of  $\cos60\degree$  

•  $\frac{1}{2}$  

•  $\frac{\sqrt{2}}{2}$  

•  $\frac{\sqrt{3}}{2}$  

•  $\sqrt{3}$  

Exact value of  $\cos540\degree$  

•  $\frac{1}{2}$  

•  $\frac{\sqrt{2}}{2}$  

•  $\frac{\sqrt{3}}{2}$  

• -1

Which maths teacher is wrong ?

• Ms. Song thinks  $\cos0\degree=\cos720\degree$  

• Mr. Garrett thinks  $\tan500\degree$  is negative

• Mr. Chen thinks  $\cos90\degree=1$  

Exact value of  $\cos\left(-300\degree\right)$  

•  $\frac{1}{2}$  

•  $\frac{\sqrt{2}}{2}$  

•  $\frac{\sqrt{3}}{2}$  

•  $-\frac{\sqrt{3}}{2}$  

Exact value of  $\tan\left(-300\degree\right)$  

•  $1$  

•  $\sqrt{3}$  

•  $\frac{\sqrt{3}}{3}$  

•  $-\frac{\sqrt{3}}{3}$  

Which TV series is Ms. Song's favorite?

(hints: the number=2*2*7*θ, and cosθ=0.3255).

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