Given f(x) = 2x + 3 and g(x) = x^2 - 1, find the composite function value (f o g)(3).
Answer and explanation
Correct answer: C. 19
- Step 1: Evaluate the inner function first: g(3) = 3^2 - 1 = 9 - 1 = 8.
- Step 2: Evaluate the outer function at this output: f(8) = 2(8) + 3 = 16 + 3 = 19.
Answer
19.
Why not the others: Option 63 computes (g o f)(3): f(3) = 2(3)+3 = 9; g(9) = 9^2 - 1 = 80 (or miscalc 63). Option 17 subtracts 2. Option 21 calculates 2(9) + 3 without subtracting 1 in g(3).
Practise more Functions, Trigonometry and Statistics.
Free questions with an explanation for every one, and full timed University of Bahrain Aptitude Test (UOB Aptitude) mock tests.
More Functions, Trigonometry and Statistics questions
- Find the inverse function f^(-1)(x) for f(x) = (3x - 5) / 2.
- If sin(theta) = 3/5 and theta is in the second quadrant (90 degrees < theta < 180 degrees), what is the value of cos(theta)?
- Simplify the trigonometric expression: (1 - cos^2(theta)) / sin(theta).
- Evaluate the exact value of tan(45 degrees) + 2 * cos(60 degrees) - sin(30 degrees).
- A right-angled triangle has an angle of 30 degrees and an adjacent side of length 12 cm. What is the length of the opposite side?
- What is the radian equivalent of an angle measuring 150 degrees?