When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Bijection - Wikipedia

    en.wikipedia.org/wiki/Bijection

    Functions which satisfy property (4) are said to be "one-to-one functions" and are called injections (or injective functions). [2] With this terminology, a bijection is a function which is both a surjection and an injection, or using other words, a bijection is a function which is both "one-to-one" and "onto". [3]

  3. Bijection, injection and surjection - Wikipedia

    en.wikipedia.org/wiki/Bijection,_injection_and...

    A function is bijective if it is both injective and surjective. A bijective function is also called a bijection or a one-to-one correspondence (not to be confused with one-to-one function, which refers to injection). A function is bijective if and only if every possible image is mapped to by exactly one argument. [1]

  4. Involution (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Involution_(mathematics)

    Any involution is a bijection.. The identity map is a trivial example of an involution. Examples of nontrivial involutions include negation (x ↦ −x), reciprocation (x ↦ 1/x), and complex conjugation (z ↦ z) in arithmetic; reflection, half-turn rotation, and circle inversion in geometry; complementation in set theory; and reciprocal ciphers such as the ROT13 transformation and the ...

  5. Schröder–Bernstein theorem - Wikipedia

    en.wikipedia.org/wiki/Schröder–Bernstein_theorem

    See the picture for examples. For an A-stopper, the function is a bijection between its elements in A and its elements in B. For a B-stopper, the function is a bijection between its elements in B and its elements in A.

  6. Bijective proof - Wikipedia

    en.wikipedia.org/wiki/Bijective_proof

    In combinatorics, bijective proof is a proof technique for proving that two sets have equally many elements, or that the sets in two combinatorial classes have equal size, by finding a bijective function that maps one set one-to-one onto the other. This technique can be useful as a way of finding a formula for the number of elements of certain ...

  7. Cantor's diagonal argument - Wikipedia

    en.wikipedia.org/wiki/Cantor's_diagonal_argument

    Define the bijection g(t) from T to (0, 1): If t is the n th string in sequence s, let g(t) be the n th number in sequence r ; otherwise, g(t) = 0.t 2. To construct a bijection from T to R, start with the tangent function tan(x), which is a bijection from (−π/2, π/2) to R (see the figure shown on the right).

  8. Isometry - Wikipedia

    en.wikipedia.org/wiki/Isometry

    Like any other bijection, a global isometry has a function inverse. The inverse of a global isometry is also a global isometry. The inverse of a global isometry is also a global isometry. Two metric spaces X and Y are called isometric if there is a bijective isometry from X to Y .

  9. Function (mathematics) - Wikipedia

    en.wikipedia.org/wiki/Function_(mathematics)

    The inverse trigonometric functions are defined this way. For example, the cosine function induces, by restriction, a bijection from the interval [0, π] onto the interval [−1, 1], and its inverse function, called arccosine, maps [−1, 1] onto [0, π]. The other inverse trigonometric functions are defined similarly.