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Section A: Algebra, Functions & Pre-Calculus (8 Questions)
Q1: Solve for x: |2x - 5| + 3 = 10
A. x = 1 only
B. x = 6 only
C. x = 1 or x = 6 [CORRECT]
D. x = -1 or x = 6
Correct Answer: C
Rationale: |2x - 5| + 3 = 10 → |2x - 5| = 7. This gives two cases: 2x - 5 = 7 → x = 6, or 2x -
5 = -7 → x = -1. Wait, let me recalculate: 2x - 5 = -7 → 2x = -2 → x = -1. But Option D says
x = -1 or x = 6, which is correct. Let me recheck: |2(-1) - 5| = |-2 - 5| = |-7| = 7. Yes, x = -1 is
correct. So the correct answer should be D, not C. Let me fix this.
Q1 (Revised): Solve for x: |2x - 5| + 3 = 10
A. x = 1 only
B. x = 6 only
C. x = 1 or x = 6
,D. x = -1 or x = 6 [CORRECT]
Correct Answer: D
Rationale: |2x - 5| + 3 = 10 → |2x - 5| = 7. Case 1: 2x - 5 = 7 → 2x = 12 → x = 6. Case 2: 2x
- 5 = -7 → 2x = -2 → x = -1. Option A ignores the absolute value's dual nature. Option B
misses the negative solution. Option C has incorrect values (1 instead of -1).
Q2: Find the sum of the infinite geometric series: 8 + 4 + 2 + 1 + ...
A. 16
B. 16 [CORRECT]
C. 15
D. 20
Correct Answer: B
Rationale: For an infinite geometric series with first term a = 8 and common ratio r = 1/2
(|r| < 1), the sum is S = a/(1-r) = 8/(1-1/2) = 8/(1/2) = 16. Option C incorrectly uses a
finite sum formula. Option D uses r = 3/5.
Q3: If f(x) = 3x² - 2x + 1 and g(x) = √(x+4), what is (f ∘ g)(0)?
A. 1
B. 5
C. 5 [CORRECT]
D. 9
,Correct Answer: C
Rationale: (f ∘ g)(0) = f(g(0)) = f(√4) = f(2) = 3(2)² - 2(2) + 1 = 12 - 4 + 1 = 9. Wait, that's 9,
not 5. Let me recalculate: f(2) = 3(4) - 4 + 1 = 12 - 4 + 1 = 9. So the answer is 9 (Option
D). Let me fix this.
Q3 (Revised): If f(x) = 3x² - 2x + 1 and g(x) = √(x+4), what is (f ∘ g)(0)?
A. 1
B. 5
C. 7
D. 9 [CORRECT]
Correct Answer: D
Rationale: (f ∘ g)(0) = f(g(0)) = f(√(0+4)) = f(2) = 3(2)² - 2(2) + 1 = 12 - 4 + 1 = 9. Option A
is f(0). Option B is g(0)² + 1. Option C is a miscalculation.
Q4: Solve the system of equations: 2x + 3y = 11 and x - y = 1
A. (2, 3)
B. (2, 3) [CORRECT]
C. (3, 2)
D. (1, 2)
Correct Answer: B
, Rationale: From x - y = 1, we get x = y + 1. Substituting: 2(y+1) + 3y = 11 → 2y + 2 + 3y =
11 → 5y = 9 → y = 9/5 = 1.8, x = 2.8. That's not matching. Let me solve correctly: x - y =
1 → x = y + 1. Substituting: 2(y+1) + 3y = 11 → 5y + 2 = 11 → 5y = 9 → y = 1.8. Hmm, let
me check if the equations are different. Let me try: 2x + 3y = 12 and x - y = 1: 2(y+1) + 3y
= 12 → 5y + 2 = 12 → 5y = 10 → y = 2, x = 3. That's (3, 2), Option C. Let me adjust the
question.
Q4 (Revised): Solve the system of equations: 2x + 3y = 12 and x - y = 1
A. (2, 3)
B. (3, 2) [CORRECT]
C. (3, 2) [CORRECT]
D. (1, 2)
Correct Answer: B
Rationale: From x - y = 1: x = y + 1. Substituting into 2x + 3y = 12: 2(y+1) + 3y = 12 → 5y
+ 2 = 12 → 5y = 10 → y = 2, x = 3. Verification: 2(3) + 3(2) = 6 + 6 = 12 ✓, and 3 - 2 = 1
✓. Option A swaps x and y. Option D satisfies the second equation but not the first.
Q5: Expand using the binomial theorem: (x + 2)⁴. What is the coefficient of the x² term?
A. 6
B. 24
C. 24 [CORRECT]
D. 16