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 The First Canadian Mathematical Olympiads 1969年第一届加拿大数学奥林匹克 1. a, b, c, d, e, f are reals such that a/b = c/d = e/f; p, q, r are reals, not all zero; and n is a positive integer. Show that (a/b)n = (p an + q cn + r en)/(p bn + q dn + r fn ).2. If x is a real number not less than 1, which is larger: √(x+1) - √x or √x - √(x-1)? 3. A right-angled triangle has longest side c and other side lengths a and b. Show that a + b ≤ c√2. When do we have equality ? 4. The sum of the distances from a point inside an equilateral triangle of perimeter length p to the sides of the triangle is s. Show that s √12 = p.5.ABC is a triangle with |BC| = a, |CA| = b. Show that the length of the angle bisector of C is (2ab cos(C/2) )/(a + b). 6.Find 1×1! + 2×2! + ... + n×n! .7.Show that there are no integer solutions to a2 + b2 = 8c + 6. 8.f is a function defined on the positive integers with integer values. Given that (1) f(2) = 2, (2) f(mn) = f(m) f(n) for all m,n, and (3) f(m) > f(n) for all m, n such that m > n, show that f(n) = n for all n. 9.Show that the shortest side of a cyclic quadrilateral with circumradius 1 is at most √2. 10. P is a point on the hypoteneuse of an isosceles, right-angled triangle. Lines are drawn through P parallel to the other two sides, dividing the triangle into two smaller triangles and a rectangle. Show that the area of one of these component figures is at least 4/9 of the area of the original triangle. 点击此处观看相关视频讲解 在方框内输入单词或词组