Question

31. Let f: R → R be a function given by f(x) = x2 + 1. Find
i) f-1(5)
ii) f-1(26​

Answer 1

Answer:

f:R→R

f(x)=x2+2

g:R→R

g(x)=x−1x

fog(x)=f(g(x))

=f(x−1x)

=(x−1x)2+2

=x2−2x+1x2+2

=x2−2x+1x2+2(x2−2x+1)

=x2−2x+1x2+2x2−4x+2

=x2−2x+13x2−4x+2

fog(2)=22−2×2+13×22−4×2+2