Let f : R → R, g : R → R be two functions defined by f(x) = x2 + x + 1 and g(x) = 1 – x2. Write fog(–2).
Formula :- (I)Let f : AB and g : B
C be two functions.
Then, the composition of f and g, denoted by g o f, is defined as the function g o f : AC
given by g o f (x) = g (f (x))
Given:-
(i)f : R → R
(ii)g : R → R
(iii) f(x) = x2 + x + 1
(iv)g(x) = 1 – x2
Fog(-2)=f(g(-2))
Fog(-2)=f(1-(-2)2)
Fog(-2)=f(-3)
Fog(-2)=(-3)2-3+1=7