Evaluate an expression from r sinθ and r cosθ Given r sin θ = 1 and r cos θ = √3, find the value of ( √3 * tan θ + 1 ).

Difficulty: Easy

Correct Answer: 2

Explanation:


Introduction / Context:
This is a trig identity/evaluation problem. Using the given r-scaled sine and cosine helps find tan θ directly by division, and the Pythagorean identity can verify consistency of r and θ.


Given Data / Assumptions:

  • r sin θ = 1
  • r cos θ = √3
  • We seek S = √3 * tan θ + 1


Concept / Approach:
Compute tan θ = (r sin θ)/(r cos θ) = 1/√3. Then plug into S. Optionally, confirm r by squaring and summing to ensure a consistent setup.


Step-by-Step Solution:

tan θ = (r sin θ)/(r cos θ) = 1/√3S = √3 * tan θ + 1 = √3 * (1/√3) + 1 = 1 + 1 = 2Check: r^2 = (r sin θ)^2 + (r cos θ)^2 = 1 + 3 = 4 ⇒ r = 2 (consistent)


Verification / Alternative check:
If tan θ = 1/√3, then θ corresponds to 30° in the principal acute range; the expression evaluates to 2 as found.


Why Other Options Are Wrong:
Values like √3 or 1 occur if tan θ is misread as √3 or 0.


Common Pitfalls:
Dividing in the wrong order (cos/sin) or forgetting that √3 * (1/√3) simplifies to 1.


Final Answer:
2

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