write the expression as the sine, cosine, or tangent of a double angle Then find the exact value of the expression. 2 sin 120 cos 120
+26367 2 sin 120 cos 120 ?
$$\\\sin{(\alpha+\beta)}=
\sin{(\alpha)}
*
\cos{(\beta)}
+
\cos{(\alpha)}
*
\sin{(\beta)}
\\
\sin{(\alpha+\alpha)}=
\sin{(\alpha)}
*
\cos{(\alpha)}
+
\cos{(\alpha)}
*
\sin{(\alpha)}\\\\
\boxed{
\sin{(2*\alpha)}=
2*\sin{(\alpha)}
*
\cos{(\alpha)}}\\\\
\sin{(2*120\ensurement{^{\circ}} )}=
2\sin{(120\ensurement{^{\circ}} )}
\cos{(120\ensurement{^{\circ}} )}=
\sin{(240 \ensurement{^{\circ}} ) =-0.86602540378$$
$$\\ \sin{(240 \ensurement{^{\circ}} )
=
\sin{(360\ensurement{^{\circ}-120 \ensurement{^{\circ} } )
=
-\sin{(120 \ensurement{^{\circ} } )
=-\frac{\sqrt{3} } {2}
=-0.86602540378$$
