Level:
Project ID:
1103212903
Source Problem:
Accepted:
1
Clonable:
1
Easy:
0
A cube \( ABCDEFGH \) with an edge length of \( 2 \) units is placed in a coordinate system (see the picture). Find an angle \( \varphi \) between the plane \( \alpha \) passing through the points \( E \), \( D \) and \( C \) and the straight line \( AF \).
Hint: An angle between a line and a plane is an angle between the line and its orthogonal projection into this plane.
\( \varphi = 30^{\circ} \)
\( \varphi = 15^{\circ} \)
\( \varphi = 45^{\circ} \)
\( \varphi = 60^{\circ} \)