関連ワード:  can a function not have an inverse    when does a function not have an inverse    can a function have an inverse and not be one to one    can a function which is not bijective have an inverse    why does a quadratic function not have an inverse    can a function have an inverse if it's not one to one    why would a function not have an inverse    what makes a function not have an inverse    why might a function not have an inverse    what functions do not have an inverse