Q:let function f from R to R define by f(t)=t^2 and let U be any nonempty open subset of R. then
a) f(U) be open
b)inverse or f(U) is open
c)f(U) is closed
d)inverse of f(U) is closed.
Q:let function f from R to R define by f(t)=t^2 and let U be any nonempty open subset of R. then a) f(U) be open b)inverse or f(U) is open c)f(U) is closed d)inverse of f(U) is closed.
Since f is continous the inverse immage of an open set is open.