Find gof and fog when f: R → R and g : R → R is defined by f (x) = x2 + 8 and g(x) = 3x3 + 1

Asked by Sakshi | 1 year ago |  59

1 Answer

Solution :-

Given, f: R → R and g: R → R

So, gof: R → R and fog: R → R

f(x) = x2 + 8  and g(x) = 3x3 + 1

(gof) (x) = g (f (x))

= g (x2 + 8)

= 3 (x2+8)3 + 1

Now, (fog) (x) = f (g (x))

= f (3x3 + 1)

= (3x3+1)2 + 8

= 9x6 + 6x+ 1 + 8

= 9x+ 6x+ 9

Answered by Aaryan | 1 year ago

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