cos^2

[Gareth56]

I've often seen in equations cos^2 then some angle so for example:-

 

cos^2 45deg. How does this work on a calculator or do you have to do something clever to work this out? Also what does cos^2 mean (other than cos x cos)?

 

Thanks

[NeonBlack]

[math]\cos^2x[/math] is an easier way to write [math](\cos{x})^2[/math]

edit: the advantage is that you will not confuse it with [math]\cos{(x^2)}[/math]

[ajb]

It just means [math](\cos x)^{2}[/math]. You use it to avoid confusion with [math]\cos x^{2}[/math].

[Gareth56]

Many thanks.

[Air]

I've often seen in equations cos^2 then some angle so for example:-

 

cos^2 45deg. How does this work on a calculator or do you have to do something clever to work this out? Also what does cos^2 mean (other than cos x cos)?

 

Thanks

 

[math]\cos ^2 x = \left(\cos x\right)^2[/math]

 

Note that [math]\cos \left(45^{\circ}\right) = \frac{1}{\sqrt{2}} \therefore \cos ^2 \left(45^{\circ}\right) = \left(\frac{1}{\sqrt{2}}\right)^2 = ... [/math]