Let f(x) : RtoR be given by f(x) = x2+3 Find 1 {x:f(x)=28} 2 The pre images of - Maths - Relations and Functions

Question

Let f(x) : RtoR be given by f(x) = x2+3 Find
1 {x:f(x)=28} 2 The pre images of 39 and 2 under 'f '

Devesh Kumar · Accepted Answer

We have,                 function R→R defined by f(x)=x2+3i
e its domain & range are Real no
1) f(x)=28=x2+3    x2=25    x=±5Therefore, for range 28 pre-image is 5 & -52) f(x)=39    x2+3=39    x2=36    x=±6Now, f(x)=2  x2+3=2  x2=-1  x=±iBut the value of 'x' is not a real value, both i & -i are complex no
s

Let f(x) : RtoR be given by f(x) = x2+3 Find 1. {x:f(x)=28} 2. The pre images of 39 and 2 under 'f '

Let f(x) : RtoR be given by f(x) = x²+3 Find
1. {x:f(x)=28} 2. The pre images of 39 and 2 under 'f '