If you mean to find 4 cos(2<em>a</em>), then recall the double angle identity for cosine:
cos(2<em>x</em>) = 2 cos²(<em>x</em>) - 1
so that
4 cos(2<em>a</em>) = 4 (2 cos²(<em>x</em>) - 1) = 4 (√3 - 1)
Answer:
I was right after all. 175°
Step-by-step explanation:
The least common denominator of 3/4, 4/5, and 2/3 can be found by finding the least common multiple of 4, 5, and 3.
List the multiples:
4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68
5: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65
3: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48, 51, 54, 57, 60, 63, 66
The least common denominator of 3/4, 4/5, and 2/3 is C. 60.
Answer:
Step-by-step explanation:
The figure given has two similar triangles: ΔABC and ΔDEF. Although the triangles are similar, their orientation is different and ΔDEF is flipped. Since the triangles are similar, their side lengths are proportional to each other. Given the orientation of the triangles, we can still see that the diagonal (hypotenuse) for the larger triangle is AC and the smaller is DF. The only answer that matches these up proportionally is the third one. Looking at the second side, BC, we can see that this matches up to the longer leg of EF on the smaller triangle. Final answer being: