+123 1. The face diagonal of a cube has length 1. Find the surface area of the cube.
2. Let , \(ABCDEFGH\) be a cube. Find \(\angle ACH \) , in degrees.
https://latex.artofproblemsolving.com/e/1/4/e143cdd3d28a9ccb962862481c5b7034ab606234.png
+37146 Find the side length of the cube using Pythagorean Theorem
x^2 + x^2 = 1^2
2 x^2 = 1
x^2 = 1/2
x = (sqrt2) / 2
Surface area = s x s x 6 (six sides ) sqrt2 /2 x sqrt2 /2 x 6 = 3 sq units
Second one: If you draw a line from A to H you will hav a triangle with all three side lengths equal....and equilateral triangle.....all of the angles in a equilateral triangle are 60 degrees
