Engineering Board Exam Reviewer · Conic Sections and Transformation of Axes · medium
Through what acute angle must the axes be rotated to eliminate the xy-term of x2-2 3,xy+3y2+4x=0? Give the answer in degrees.
- 60°
- 15°
- 45°
- 30°
Answer
D. 30°
Solution
2 =B/A-C=-2 3/1-3= 3 2 =60°, so =30°.
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