Math Analysis Angle addition and double angles

Simplify:

 $Cos35\degree Cos10\degree-Sin35\degree Sin10\degree$  

•  $Cos25\degree$  

•  $Sin25\degree$  

•  $\frac{\sqrt{2}}{2}$  

•  $-\frac{\sqrt{2}}{2}$  

Simplify

 $Sin200\degree Cos5\degree+Cos200\degree Sin5\degree$  

•  $Sin205\degree$  

•  $Sin195\degree$  

•  $Cos205\degree$  

•  $Cos195\degree$  

 $\frac{\tan\left(\frac{13\pi}{18}\right)+\tan\left(\frac{\pi}{36}\right)}{1-\tan\left(\frac{13\pi}{18}\right)\tan\left(\frac{\pi}{36}\right)}$  

•  $\frac{\sqrt{2}}{2}$  

•  $-\frac{\sqrt{2}}{2}$  

• 1

• -1

Simplify and evaluate

 $Cos^2105\degree-Sin^2105\degree$  

•  $\frac{-\sqrt{3}}{\ \ \ \ 2}$  

•  $\frac{\sqrt{3}}{\ 2}$  

•  $\frac{-1}{\ \ 2}$  

•  $\frac{\ \ 1}{\ \ 2}$  

Simplify

 $2Sin20\degree Cos20\degree$  

•  $Sin20\degree$  

•  $Cos20\degree$  

•  $Sin40\degree$  

•  $Cos40\degree$  

Which of the following is the first step of verifying

 $Sin\left(\pi-x\right)=Sinx$  

•  $Sin\pi Cosx-Cos\pi Sinx$  

•  $Sin\pi Cosx+Cos\pi Sinx$  

•  $Cos\pi Cosx-Sin\pi Sinx$  

•  $Cos\pi Cosx+Sin\pi Sinx$  

Simplify and evaluate

 $2Cos^2\left(\frac{\pi}{3}\right)-1$  

•  $\frac{\sqrt{3}}{2}$  

•  $-\frac{\sqrt{3}}{2}$  

•  $\frac{1}{2}$  

•  $-\frac{1}{2}$  

Simplify and evaluate

 $\frac{2\tan\left(\frac{\pi}{3}\right)}{1-\tan^2\left(\frac{\pi}{3}\right)}$  

• -1

• 1

•  $-\sqrt{3}$  

•  $-\frac{\sqrt{3}}{3}$  

Given

 $Sin\theta=-\frac{7}{25}\ in\ Quad\ III\ ,\ find\ Cos2\theta$  

•  $\frac{527}{625}$  
  

•  $\frac{576}{625}$  
  

•  $\frac{49}{625}$  

• 1

Given $Sin\alpha=-\frac{7}{25}in\ Quad\ III\ and\ Cos\beta=\frac{3}{5}in\ QuadIV,\ find\ Sin\left(\alpha-\beta\right)$  

•  $-\frac{85}{125}$    

•  $\frac{85}{125}$  
  

•  $\frac{117}{125}$  
  

•  $-\frac{117}{125}$