A triangle has two corners with angles of # pi / 4 # and # pi / 8 #. If one side of the triangle has a length of #8 #, what is the largest possible area of the triangle?

1 Answer
Mar 12, 2017

32+16#sqrt2#

Explanation:

To create a triangle with maximum area, we want the side of length #8# to be opposite of the smallest angle. Let us denote a triangle #DeltaABC# with #angleA# having the smallest angle, #frac(pi)(8)#, or #22.5#. Thus, #BC=8#.

From here, we may find the final angle, (#180-45-22.5=112.5#), and apply law of sines to find side #AB#.

#frac(sin(22.5))(8)=frac(sin(112.5))(x)#, where #x# is the length of #AB#.

Now, we may find the area of the triangle through the formula #Area=frac(1)(2)ab sin(C)#, or #frac(1)(2)AB*BC sin(B)=32+16sqrt2#.