Answer to Question #97545 in Discrete Mathematics for Jflows

Question

5.Let f be a function of A into B. If every member of B appears as the image of at least one element of A, then we say the function f is
a.surjective functions
b.constant function
c.injective functions
d.identity functions

6.Let f be a function of A into B, and let \\(b\\in B\\). Then \\(f^{-1}(b)=\\left \\{ x:x\\in A;f(x)=b \\right }\\)\n defines…
a.injective functions
b.constant function
c.inverse function
d.constant fnction

Answer 1

5.By definition, a function from A to B is called surjective if for every member b from B there is at least one element a in A so that f(a)=b. So the answer is a);

6.A function $f^{-1}(b),$ that finds all elements a in A so that f(a)=b, is called inverse function. So the answer is c);