let n be Element of NAT ; :: thesis: for r being real number
for y being Point of (TOP-REAL n) st y in cl_Ball (0.REAL n),r holds
|.y.| <= r

let r be real number ; :: thesis: for y being Point of (TOP-REAL n) st y in cl_Ball (0.REAL n),r holds
|.y.| <= r

let y be Point of (TOP-REAL n); :: thesis: ( y in cl_Ball (0.REAL n),r implies |.y.| <= r )
assume y in cl_Ball (0.REAL n),r ; :: thesis: |.y.| <= r
then |.(y - (0.REAL n)).| <= r by Th8;
hence |.y.| <= r by JORDAN2C:13; :: thesis: verum