Question

Let U be the set of all triangles in a plane. If A is the set of all triangles with at least one angle different from 60°, what is? friends plzzz explain me this....

Answer 1

lets think buddy : - 

here is given that A is the set of all triangles  with at   least  one angle is different  

and here U is the set of all triangles in a plane  which means U has same angle of A so that it can make all the triangles in a plane as given in ur question which means  all angles of U are of 60 °

so we can conclude that U is an equilateral triangle  

HOPE THIS HELPS YOU 

cheers !