103 Trigonometry Problems

Chebyshev Polynomials
Glossary 201
Let {T n (x)} ∞ n=0 be the sequence of polynomials such that T 0(x) = 1, T 1 (x) = x,
and T i+1 = 2xT i (x) − T i−1 (x) for all positive integers i. The polynomial T n (x) is
called the nth Chebyshev polynomial.
Circumcenter
The center of the circumscribed circle or sphere.
Circumcircle
A circumscribed circle.
Convexity
A function f(x)is concave up (down) on [a,b] ⊆R if f(x)lies under (over) the
line connecting (a 1 ,f(a 1 )) and (b 1 ,f(b 1 )) for all
a ≤ a 1