2.
設
0
x2
，求
tan2x−9tanx+1=0之各根總和為多少？
112.8.22補充
若
0x2，則滿足
tan2x−9tanx+1=0的所有
x值之和為
。
(111高中數學能力競賽 第一區(花蓮高中)筆試二試題，
https://math.pro/db/thread-3782-1-1.html)
Find the sum of the roots of
tan2x−9tanx+1=0 that are between
x=0 and
x=2 radians.
(A)
2 (B)
(C)
23 (D)
3 (E)
4
(1989AHSME，
https://artofproblemsolving.com/ ... Problems/Problem_28)
