Two corners of a triangle have angles of (3 pi )/ 8 and ( pi ) / 2 . If one side of the triangle has a length of 2 , what is the longest possible perimeter of the triangle?

1 Answer
Jan 29, 2018

P = 4.8284 + 5.2263 + 2 = color(purple)(13.0547)

Explanation:

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Given A = (3pi)/8, B = (pi)/2

C = pi - (3pi)/8 - pi/2 = pi/8

To get the longest perimeter, side 2 should correspond to the least angle pi/8

a / sin ((3pi)/8) = b / sin (pi/2) = 2 / sin (pi/8)

a = (2 sin ((3pi)/8)) / sin (pi/8) = 4.8284

b = (2 sin (pi/2)) / sin (pi/8) = 5.2263

Longest Perimeter P = a + b + c

P = 4.8284 + 5.2263 + 2 = color(purple)(13.0547)