To pick some of the objects from a larger set; in counting, choosing r objects means taking them without regard to order.
例文
話し言葉 We need to choose 3 of the 10 students, and order doesn't matter, so that's 10 choose 3. 10 人の生徒から 3 人を選ぶ。順序は関係ないので ₁₀C₃ だ。
書き言葉・答案 In how many ways can a committee of 4 be chosen from 7 men and 5 women if it must include at least one woman? 男子 7 人、女子 5 人から 4 人の委員を選ぶとき、女子を少なくとも 1 人含む選び方は何通りあるか。
Khan Academy Algebra / Khan Academy AP Calculus / Khan Academy AP Statistics / Khan Academy Middle School (6th-8th Grade, Pre-Algebra) / MIT OCW 18.01 Single Variable Calculus / MIT OCW 18.02 Multivariable Calculus / MIT OCW 18.03 Differential Equations / MIT OCW 18.06 Linear Algebra / MIT OCW 6.042 Mathematics for Computer Science / 3Blue1Brown / blackpenredpen / NancyPi / The Organic Chemistry Tutor / PatrickJMT / Professor Leonard
取得元(書き言葉)
MIT OCW lecture notes / OpenStax Algebra and Trigonometry 2e / OpenStax Calculus Vol 1-3 / OpenStax Elementary Algebra 2e / OpenStax Intermediate Algebra 2e / OpenStax Introductory Statistics 2e / OpenStax Prealgebra 2e / OpenStax Precalculus 2e