geometric-proof-of-integer-sum-formula

Precalculus: We give an alternative proof that 1+ 2 + ... + n = n(n+1)/2. Our motivation is to explain the 1/2 factor in terms of the area of a triangle.

Tagged under: Mathematics,precalculus,integer,sum,formula,arithmetic,sequence,area,triangle,square

Clip makes it super easy to turn any public video into a formative assessment activity in your classroom.

Add multiple choice quizzes, questions and browse hundreds of approved, video lesson ideas for Clip

Make YouTube one of your teaching aids - Works perfectly with lesson micro-teaching plans

1. Students enter a simple code

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4. You review and reflect

* Whiteboard required for teacher-paced activities

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Clip

Turn any public video into a live chat with questions and quizzes

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