1.1tanc =-tan (a+b) =-(tana+tanb)/(tanatanb) =-5, from which c = (pai) -arctan5 is obtained.

The minimum angle from 1.2 to the shortest side: the minimum angle is B. sinC= = root number 26 divided by 5 sinB= = root number 10 used to derive the edge B = 125 divided by root number 13.

2( 1, root number 2) is (open 1) to close (middle root number 2) (because a+c = 90 degrees, then the largest isosceles right triangle. )