Maths Tricks You Must Know | Fastest Calculation Methods

One Thousand and One | Numberblocks COURSE - Level 5, Blue (S4 E29)

Q) Let A = R – {5} and B = R – {1}. Consider the function f: A → B, defined by f(x) = (𝑥−3)/

Q) Show that 𝑓:𝑅_+→[−5,∞) given by 𝑓(𝑥)=4𝑥^2+4𝑥−5 is both one-one and onto where 𝑅_+=[0,∞).

Q) Show that a function f: R → R defined by f(x) = 2𝑥/(1+𝑥^2 ) is neither one-one nor onto.