Verification will take sometime. We had this in our semester test this time.
I marked d) for 1 too. But didnt mark any for the 2nd.
Consider an arbitrary function f:X→Y. It includes two important set mappings. If A is a subset of X, then its image f(A) is the subset of Y defined by f(A)={f(x) : x ε A}. Similarly, if B is a subset of Y, then its inverse image f-1(B) is a subset of X defined by f-1(B)={x : f(x) ε B }.
1. Which of the following is not true?
a) A_{1}\subseteq A_{2} \Rightarrow f(A_{1})\subseteq f(A_{2})
b) f\left( \bigcap_{i=1}^{n}{A_{i}}\right) =\bigcap_{i=1}^{n}{f(A_{i}})
c) f\left( \bigcup_{i=1}^{n}{A_{i}}\right) =\bigcup_{i=1}^{n}{f(A_{i}})
d) f(A)\subseteq f(A^{c}) iff f is onto where A_{i}\subset X
2. Which of the following is not true?
a) A=f^{-1}(f(A))
b) f^{-1}(Y)=X
c) f^{-1}(\cup_{i}B_{i} )=\cup_{i}f^{-1}(B_{i})
d) f^{-1}(\cap_{i}B_{i} )=\cap_{i}f^{-1}(B_{i}) \: where \: B_{i}\subset Y
Most of the time goes in understanding what these freaking symbols mean over here. Please a detailed solution of what is happening here would be great.
PPLLLLLLEAAAAAAASSSSSEEEEEEE! [3]
Verification will take sometime. We had this in our semester test this time.
I marked d) for 1 too. But didnt mark any for the 2nd.
even i think d answer to d first will b d), but can't get an air of d second...d question itself seems confusing...
ask nishant sir...he will anyway answer it today...:) :-)
No one I guess. Sir, if you could please tell what these symbols do exactly over here!
They stand for intersection and union of many sets...
like summations of many numbers....
Just now, I came to know that you are A.Kothari. I was mistaking you as Ashish Bhaiya.. (You also wrote above 'semester' so I thought if it were Ashish Bhaiya)
That's why I wondered why is he asking such questions..