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cecbos97
The point (12, 5) is on the terminal side of an angle θ. What is cos θ ?
\(\large \begin{array}{ccllll} (&12&,&5)\\ &\uparrow &&\uparrow \\ &x&&y \end{array}\) thus |dw:1408396503470:dw| so... what's the hypotenuse? notice is a right triangle, so you can use the pythagorean theorem to get that keep in mind your SOH CAH TOA ,thus \(\bf cos(\theta)=\cfrac{adjacent\ side}{hypotenuse}\)
\[\cos \left(\tan ^{-1}\left(\frac{5}{12}\right)\right)=\frac{12}{13} \]