At:
is intersection implies exists element122111
1.
T: Type
2.
eq: {T=}
3.
L: T List
4.
M: T List
5.
u: T
6.
v: T List
7.
v(eq)M (x:{x:T| x(eq) v }. x(eq) M)
8.
xv.x(eq) M
9.
v(eq)M
10.
x: {x:T| x(eq) v }
11.
x(eq) M
x:{x:T| if eq(x,u) true else x(eq) v fi }. x(eq) M
By:
With x (Analyze 0)
Generated subgoal: