CA Foundation · Quantitative Aptitude · Sets, Relations and Functions, Limits and Continuity
If f(x) = x² + 1 and g(x) = 3x − 2, what is the value of (f∘g)(2) − (g∘f)(2)?
The difference is 4, which is not among the options as listed.
- A1
- B−1Correct
- C10
- D11
Explanation
g(2) = 4, so f(g(2)) = 16 + 1 = 17. f(2) = 5, so g(f(2)) = 15 − 2 = 13. Difference = 17 − 13 = 4. Check options: 4 is not listed in order, so recompute: f(g(2)) = f(4) = 17, g(f(2)) = g(5) = 13, difference 4.
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