+0  
 
0
214
2
avatar

sin^2(-x)+cos^2(-x)

Guest Mar 13, 2015

Best Answer 

 #2
avatar+18843 
+5

sin^2(-x)+cos^2(-x)

$$\boxed{
\begin{array}{ccc}
\sin(-x) &=& -\sin{x}\\
\cos(-x) &=& \cos(x)
\end{array}
}\\\\\\
\sin^2(-x)+\cos^2(-x)\\
=[-\sin(x)]^2+[cos(x)]^2\\
=\sin^2(x)+\cos^2(x)\\
=1$$

heureka  Mar 13, 2015
Sort: 

2+0 Answers

 #1
avatar+81090 
+5

sin^2(-x)+cos^2(-x)

Let -x  = θ

So

sin^2 (θ) + cos^2 (θ)  = 1   {this is just a basic identity}

 

  

CPhill  Mar 13, 2015
 #2
avatar+18843 
+5
Best Answer

sin^2(-x)+cos^2(-x)

$$\boxed{
\begin{array}{ccc}
\sin(-x) &=& -\sin{x}\\
\cos(-x) &=& \cos(x)
\end{array}
}\\\\\\
\sin^2(-x)+\cos^2(-x)\\
=[-\sin(x)]^2+[cos(x)]^2\\
=\sin^2(x)+\cos^2(x)\\
=1$$

heureka  Mar 13, 2015

28 Online Users

avatar
avatar
avatar
avatar
avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details