Let A = [–1, 1]. Then, discuss whether the following functions defined on A are one-one, onto or bijective:
h(x) = x |x|
Given that, A = [–1, 1]
let h(x1) = h(x2)
⇒ x1|x1|= x2|x2|
if x1,x2 >0
⇒ x12 = x22
⇒ x1= x2
if x1,x2 < 0
⇒ x12 = x22
⇒ x1= x2
⇒ h is one-one.
Let h(x) = y
⇒ y = x |x|
⇒ y = x2
Thus, for each y co domain there exists x in domain.
⇒ h is onto.
Hence, h is one one and onto.
So, h is bijective.