Answer:
A. DEF where and .
Step-by-step explanation:
At first we must keep in mind that two triangles are similar when they have same angle configuration, that is, each pair of angles is congruent. If ABC and DEF, then and . Hence, and .
In a nutshell, correct answer is A.
Graph
sin(π/8) = (1/2)√(2-√2)
Using the half-angle formula ...
We can let θ = π/4 and simplify the result as follows: