6. Indicate which of the three properties 1) everywhere dened, 2) onto, and 3) one-to-one, are satised by the following functions: function everywhere dened onto one-to-one a. szaz, f(m) = M b. f : R>R, f(m) =lna: c. f : R>R, f(m) = 10$ 7. For the following, either prove or disprove using a. counter example: (a) If f : R > R is dened as f(a:) = 2:2 + 2:1: 3,V:c E R, then f is not invertible. (b) If f : R > R is a one-to-one function, and g : R > R is a one-toone function, then f + g is also one-to-one