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Answer: ASet 3: Trigonometry (Intermediate)
Explanation
PROBLEM
Intriguingly, in a right triangle, the opposite side is 5, adjacent side is 12, and hypotenuse is 13. Find cos(angle).
In a right triangle, the opposite side is 5, adjacent side is 12, and hypotenuse is 13. Find cos(angle).
A.✓ Correct
12/13
B.
5/12
C.
13/5
D.
12/13
Detailed Explanation
[Variation 2] Choice A is the best answer. cos = adjacent/hypotenuse = 12/13
Why others are wrong:
B: 5/12 is incorrect because it does not satisfy the equation.
C: 13/5 is incorrect because it does not satisfy the equation.
D: 12/13 is incorrect because it does not satisfy the equation.