Question

$f:A\to B$ defined by f(x) = 2x+3 and if A = {-2,-1,0,1,2} B = {-1,1,3,5,7} then which type of function is f?

• A. One-one
• B. Onto
• C. Bijection
• D. Constant

Answer 1

Answer: (C)

Bijection

As the function is from set A to set B, let us find the range of the elements of A.
$f\left(x\right)=2x+3$
$=>f(-2)=2(-2)+3=-1$
$=>f(-1)=2(-1)+3=1$
$=>f\left(0\right)=2\left(0\right)+3=3$
$=>f\left(1\right)=2\left(1\right)+3=5$
$=>f\left(2\right)=2\left(2\right)+3=7$
We can see that each element of A is mapped to only one and different element of B
Hence, the function is a Bijection function.